FAQ

A final design has yet to be determined by the European organisation. The assignment for the Einstein Telescope EMR Project Office in this Euregio involves a triangular tunnel with arms measuring 10 kilometres in length (3 times). It is an underground observatory that will be located at a depth of 250 to 300 metres. Underground spaces/rooms will be located at the three corners. Laser beams will run through the 10-kilometre arms (the tunnel tubes). A laser beam will be split into two beams, which will be reflected by mirrors at the ends of the arms in the underground chambers. A lift will run from the three corners to ground level. These shafts will be used to carry out maintenance work inside the tunnel and to install new innovations as they become available.

The Einstein Telescope will soon provide scientists with an underground detector (observatory) where gravitational waves can be studied. It is expected that it will then be possible to ‘look back’ to shortly after the Big Bang. This ten times more accurate measurement facility than its predecessors will provide a lot of new information about the origin of our universe.
Ten times more accurate means that a thousand times more gravitational waves can be measured. Where it is now once a week, the Einstein Telescope will be able to measure a gravitational wave a hundred times a day. Exactly what information all this will yield and where it could lead, cannot be said in advance. But scientists around the world are convinced that it will yield a lot.

When European countries, united in ESFRI (European Strategy Forum on Research Infrastructures), agree that a research facility is of great importance for science, the plan for such a facility is placed on the so-called ESFRI Roadmap. This is a European priority list in which the scientific community indicates which projects are the most important. As such, they are also the projects on which science money would be responsibly spent. European scientists and ministries decided in 2021 that this project would be on the European Roadmap and should be brought to realisation within 10 years.

That is impossible to say at this stage. We are optimistic, but the reality is that we are still in the feasibility phase. In 2021, European scientists and ministries decided that this project should be included in the European roadmap (ESFRI) and should be realised within 10 years. These scientists – united in the Einstein Telescope Organisation (ETO) – and ministries – united in the BGR – are now working out the project and the further timeline for its realisation and the choice of location. Not only our Euregio Meuse-Rhine, but also the Italian island of Sardinia and the German state of Saxony are keen to build the telescope. In the meantime, our Euregio is already working hard on a bid book to demonstrate the technical, organisational and financial feasibility. This bid book will be ready by the end of 2026. According to the current planning at European level, the choice of location between “our” border region in Euregio Meuse-Rhine, Sardinia and Saxony will follow in the course of 2027.

The soil in this region appears to be suitable for the construction of the Einstein Telescope. For measurements of gravitational waves, it is important that as little noise as possible penetrates the soil. Noise is caused, for example, by heavy industry, railways or mining. The soft top layer of the soil dampens the noise present and the hard rock layers underneath appear to be suitable for the construction of the tunnel.
Another important factor is that the larger surrounding Euroregion has strong research institutes and high-tech companies that make the science and realisation of the Einstein Telescope possible. Think of the top-tech triangle of Leuven-Eindhoven-Aachen, which includes the universities of Liège, Hasselt and Maastricht. This is also an area with good infrastructure connections and an attractive international living and business climate.
This puts our Euregio in a favourable starting position. The initial geological and economic feasibility studies have proved positive. Institutes and companies are already working together intensively in a cross-border R&D programme. The project office is working on the studies and preparations necessary for a bid book.

The project will remain in the feasibility phase for the next few years. During this phase, it must become clear whether the Einstein Telescope can actually be built in the Euregio Meuse-Rhine. A great deal of research is still being carried out in the feasibility phase. This includes geological research into the soil in order to find the ideal location for the three corners within the search area. At the same time, all aspects related to the construction of an underground observatory are being examined. This goes far beyond mere construction issues. Where will the excavated soil go? What will the logistics look like? What does this mean for the surrounding area? Can the Einstein Telescope be built in a sufficiently sustainable manner? Are there sufficient financial commitments? These are all questions to which answers are currently being sought.

The Netherlands, Belgium and North Rhine-Westphalia are working on a joint bid. Germany (the Federal Republic) has yet to endorse the final location choice, but did place the Einstein Telescope on its list of important scientific projects in July 2025.
Within the Einstein Telescope EMR project office, experts from various disciplines and institutes are working together on parts of the feasibility study. For example, they have looked at the differences in planning laws and regulations and their significance for the Einstein Telescope project.
Composite teams from the three countries and institutes are also active in the areas of sustainability research, drilling, seismic research, participation and energy.

At present, 11 European countries have thrown their weight behind the Einstein Telescope initiative. These are Belgium, the Netherlands, Italy, Spain, the United Kingdom, Poland, Austria, France, Croatia and Greece. Germany, as the eleventh country, currently has an observer role, but is expected to join in the not too distant future.
These countries, united in the so-called Board of Representatives, will decide on the location at government level in 2027.

The starting position of our euregio for locating the Einstein Telescope here is excellent. For instance, initial soil studies have proved favourable. Moreover, the peaceful landscape provides the guarantees needed for good scientific measurements. And the larger surrounding Euroregion has strong research institutes and high-tech companies that make science and the realisation of the Einstein Telescope possible. This is also an area with good infrastructure connections and an attractive international living and business climate.

And then what does it deliver in the border area itself? Belgium, the Netherlands and Germany, and in particular this Euroregion where the underground observatory will hopefully be built, will be leading the world in science. The knowledge infrastructure in the Meuse-Rhine Euroregion is already in good shape with the top technology area between Leuven, Aachen, Eindhoven, Maastricht and also with those in the Liège region, but it will then become many times stronger. In a rapidly changing world where practical application of knowledge plays an increasingly decisive role, this is important. With the Einstein Telescope, there will also be a magnet to keep and attract top talent in the field of natural sciences and engineering in our Euroregion. And the Einstein Telescope also turns out to generate a multitude of economic activities and jobs for the Euroregion. Not just for science itself. It also provides jobs for practically skilled people in the surrounding area and gives an extra boost to regional and local amenities such as retail.

Moreover, the scientific and economic activities will not take place underground or in the landscape, but rather at the research institutes and companies in the Euroregion, where preparations are already underway. For example, research shows that every euro invested in the Einstein Telescope will generate three times the economic added value. This will also benefit the region in social terms. Furthermore, research shows that the arrival of the Einstein Telescope will create an estimated 500 direct and 1150 indirect jobs at all educational levels. The Einstein Telescope thus provides opportunities for future generations. It is an engine for a healthy Euroregion and for prosperity, which in turn can contribute to (more) well-being.

As Euregio Meuse-Rhine, we are not the only candidate to build the Einstein Telescope. Sardinia in Italy and the German region of Saxony have also put themselves forward as candidates and are also working on a feasibility study.
The final decision will be made at government level by the European countries that have backed the Einstein Telescope project. The committee that will decide on the location and the procedure for this still need to be further developed. What is clear is that it will consist of representatives from the countries that have shown their support for the project. These are currently the Netherlands, Belgium, Italy, Austria, France, Poland, Spain, the United Kingdom, Greece and Croatia. Germany currently has observer status.

Apart from the benefits that the Einstein Telescope will bring to science, there are other benefits to be mentioned. In developing the Einstein Telescope, new techniques will be developed that will also be useful to us in everyday life. Innovations that will ultimately lead to advances that benefit everyone in everyday life. Previous research infrastructures such as CERN have made these revolutionary discoveries that have also changed our daily lives. Think of the internet, GPS or medical scanners and radiation equipment. Experience shows that these more derivative benefits are often just as important as the benefits the project brings to science.

The candidacy is primarily the responsibility of the participating countries. In our case, that means Belgium, the Netherlands and Germany.
At European level, agreements on the organisation and financing are made by ministries. The candidate countries will have to present an attractive proposal to other countries, including in financial terms. This is because the candidate countries and the region where it will be located will also be the first to benefit from the infrastructure, both scientifically and economically. A few years ago, the construction of the Einstein Telescope was estimated to cost 2 billion euros. In 2022, the Dutch government reserved approximately €1 billion for the preparations and construction through the National Growth Fund. The German state of North Rhine-Westphalia has indicated that it is willing to contribute to the construction if the German government in Berlin says “yes” to the project. Flanders has reserved €200 million for the Einstein Telescope.
The Einstein Telescope is expected to operate for 50 years. It is not yet clear how the operating costs will be divided and what contributions can be expected from the other participating countries.

The current planning assumes that construction will start in 2028 at the earliest. If it becomes clear that the Einstein Telescope will be built in this region, three years will then be allowed for the preparations for construction and the spatial and licensing procedures. For construction itself, seven years are planned: between 2028 and 2035.

A major construction project like the Einstein Telescope will not be without inconvenience. No mistake about that; that is impossible with such projects. We realise that we are ‘guests’ in a beautiful, nature-rich area. This also means that we will take this into account as much as possible when working out our plans. Moreover, we will obviously have to comply with rules, regulations and laws later on, as is the case with any major building project.

Once the exact location in this Euroregion is in sight, we can make more concrete plans for construction. One of the central questions here is how to minimise inconvenience to residents in the area. For example, a logistics study is under way into the use of the railway yard in Montzen (Wallonia). Transport by rail would significantly reduce the number of truck movements.

Yes. We see that as a safeguard to properly weigh all interests in such a large project to ultimately arrive at the best choices. In doing so, we look first and foremost at feasibility in relation to spatial plans and ordinances in which many environmental issues are laid down. During the implementation of the feasibility studies, we are also in direct contact with municipalities and residents in the direct vicinity to make sure they are informed. The environmental impact assessment is also prepared during the feasibility phase.

Sustainability is an important issue. An exploratory study has been carried out on how sustainability – in the broadest sense of the word – can play a role in the preparations, construction, period of operation and even as early as decommissioning of the Einstein Telescope. The topic of sustainability thus becomes an important building block for the feasibility study. This is one of the topics that will naturally also be reflected in the environmental impact assessment.

The Einstein Telescope is a highly sensitive measuring instrument. A noise-free environment is important for the Einstein Telescope to function properly. Initial underground measurements taken in 2019 showed that the top layer has a dampening effect and that the noise level in the hard subsoil is therefore sufficiently low. This supports the assertion that the Euregio Meuse-Rhine is a promising candidate location. The measurements also showed that there is little margin for additional new sources of vibration. Previous studies have shown that wind turbines are a significant source of noise (known as seismic impact).
Nikhef, the scientific partner in the Einstein Telescope EMR project office, has therefore asked the responsible authorities in the search area for the telescope to provide guarantees that no new activities will take place in the search area for the Einstein Telescope and a 10-kilometre zone around it that could lead to new vibration sources.
At the request of Nikhef, the (Dutch) Province of Limburg has established rules for wind turbines and excavations. Wind turbines in and around the search area for the Einstein Telescope are excluded; excavations are only possible if it can be demonstrated that they will not interfere with the Einstein Telescope.
The Flemish authorities have sent a letter confirming that they will exclude these developments and have indicated that they will be vigilant to ensure that such developments do not occur in Flanders. They have also announced their formal commitment to oppose any ongoing initiatives. The Walloon authorities have also recognised the importance of this issue and the Walloon government will investigate the technical compatibility of the Einstein Telescope and wind turbines. If this investigation shows that they are not compatible, new wind energy projects would be excluded until, at least, the location for the Einstein Telescope has been chosen. For this reason, in April 2023, the Belgian Council of State revoked several permits for wind turbine plans in the Walloon part of the search and protection area. NRW has given its commitment that no activities will take place in the border region (Aachen) that are detrimental to (the candidacy of) the Einstein Telescope.
In the meantime, the complex geology in combination with other relevant factors in the Meuse-Rhine Euroregion is being further investigated in order to determine the optimal location for the Einstein Telescope in this Euroregion. It is expected that this information will also enable better simulation of the effects of wind turbines. The aim is to gain a better understanding of how mitigating (protective) measures can be implemented to suppress noise and ensure the proper functioning of the Einstein Telescope.

Test drillings are part of the feasibility study. This study will further investigate whether the Einstein Telescope can be built in the border region of Belgium, the Netherlands and Germany.
Test drilling is used to map a geological profile of the subsoil. This provides information about, among other things, the composition of the subsoil and its stability.
In 2024, 11 drillings were carried out. In 2025, there will be 3 drillings for the time being.

A drilling rig is used to extract rock samples from the ground to an average depth of 250 to 400 metres. The drilling method can be compared to removing the core from an apple with an apple corer.
The samples (cores) are approximately 100 centimetres long and have a diameter of 10-15 centimetres. These rods are registered and then analysed and stored elsewhere.

In principle, very little. We are doing our utmost to drill in an environmentally friendly manner. This was one of the criteria when choosing the drilling company. Through traffic will not be affected.
The drilling locations are temporary and comparable in size to a house construction site. All locations are in rural areas.
Drilling the first few metres may cause some noise during the first few days. Once the drill is deeper in the ground, this will no longer be the case. Traffic measures will not be necessary, or will only be necessary for a short time, during the delivery and collection of the drilling rig and other equipment.

Including the setting up and dismantling of the temporary site, drilling takes an average of 10 to 12 weeks. Of these, the actual drilling takes about 5-7 weeks.

The release of nitrogen will be limited as much as possible. We will drill both electrically and with a diesel-powered drill.

Wherever possible, we drill electrically. This is generally faster, so the entire drilling process takes less time. The generator for the electric drill is powered by a generator, which uses diesel as fuel. To reduce emissions, we use the best available technology in the form of an economical, environmentally friendly generator.

We also work with a drilling setup on a truck. Here, the drilling machine is powered by the truck’s diesel engine. The nitrogen released here is reduced as much as possible with a NoNoX filter.

Consultations have (been) held with the private landowners, land users, municipalities involved and other authorities about the necessary permission, permit or exemptions. This varies by country and location. Obviously, we cannot start drilling until this has been arranged.

No, in addition to the drilling, seismic and electrical resistivity measurements are also planned. Seismic measurements work with sound waves that map hard layers in the soil. This is similar to taking an ultrasound in a hospital.

Resistivity measurements use weak current to determine the electrical resistance of various soil layers. This gives a picture of which types of rock to expect.

Both methods help to further map the structure of the subsurface.

Whereas drilling and borehole measurements provide an accurate picture of the subsurface at the drilling site, seismic and resistivity measurements complement that in the area of the drilling sites.

Additional drilling will follow at a later date, which will then focus more specifically on the possible locations for the three corner sites. It is still unknown how much drilling will then take place and at which locations.

When work permits, this will be possible at a number of times under the supervision of our site managers. We publish those dates, times and location here. These times may change at the last minute, so please check the website shortly beforehand.

We are currently in the feasibility phase, which must definitively demonstrate and substantiate that this region is ready in all respects for the construction of the Einstein Telescope. In addition, Sardinia and Saxony are the second and third candidates for the construction of the Einstein Telescope. The decision on where the Einstein Telescope will be built will be made in 2027. Preparations for the construction itself will begin after that.

The answer to that is unequivocal: no. The underground observatory requires such stable and noise-free soil. This site would never have been considered if this border region had an increased risk of earthquakes and hence earthquake damage. Nor does the construction and subsequent use of the telescope at a depth of about 250 metres in the ground increase the risk of earthquakes. Compare it to a hard stone, into which a hole is drilled from one side to the other. That hole is very small in relation to the whole stone. That does not make that stone softer or more unstable. This is also how the construction of the Einstein Telescope should be seen in relation to the whole rock. Another comparison is with a car tunnel through a high mountain, e.g. the Gothard tunnel in Switzerland: the tunnel does not make the mountain unstable.

A comparison with earthquakes in Groningen due to gas extraction is also out of the question here. In Groningen, gas is under pressure in a porous layer deep below the surface. This layer owes its solidity to the presence of that gas. When you start extracting that gas, that porous layer becomes more unstable and that can lead to subsidence and earthquakes. That soil can become more unstable as a result, as has unfortunately been seen in Groningen.

Nor is there any comparison between the Einstein Telescope and mining in southern Limburg. In mining, entire layers were extracted from the soil, relatively close to the surface. This is comparable to gas extraction in Groningen: where the soil in Groningen has become weak or unstable by removing entire layers of gas, the same was the case in the South Limburg region by removing coal layers.

On this too we can be clear: no. In no way has a relationship of the Einstein Telescope with nuclear energy ever been discussed; not during construction, not during operation, nor for the period after decommissioning 50 years later.

We have indicated that once the Einstein Telescope is built, little of the underground observatory will be visible in the immediate area. While most of the people who will soon work for the telescope will do so in the Euroregion, they will not do so in and around the observatory itself. For example, a research centre is more likely to be set up in one of the larger, surrounding cities. Housing will often focus on those cities. In addition, the spatial layout and housing supply also differs in the border region between the three countries. The housing market will obviously be monitored towards 2035, and there is still plenty of room to manage this.