Struve Geodetic Arc, Tartu University, Estonia

Old observatory Tartu University Estonia
The Old Observatory at Tartu University.

The Struve Geodetic Arc is a series of triangulations done by Tartu University astronomer and geographer Friedrich Georg Wilhelm Struve between 1816 and 1855. The measurement of the meridian, which used the observatory at Tartu University in Estonia as its base point, represented the first accurate measuring of a long segment of a meridian. This helped to establish the exact size and shape of the planet and marked an important step in the development of earth sciences and topographic mapping.

Struve was an astronomer at Tartu University and did important early astronomy work on the nature of binary stars. But his actual thesis work was on determining the exact coordinates of the Tartu Observatory. This, indirectly, led to his geodesic project.

You can certainly click the link above, and here for some more info on the Geodesic Arc, and it's status as a Unesco World Heritage Site.

Some posts on Travel Past 50 may contain affiliate links. If you buy something through one of those links, we may earn a small commission. As an Amazon associate, we earn from qualifying purchases.

I, with my limited knowledge of math and physics, find the work of people such as Struve, accomplished around 200 years ago, simply astonishing. We love visiting Unesco sites in general, but the scientific ones are maybe even more interesting to me than the artistic and historical ones.

For an interesting read on geodesic mapping, I also suggest a book about a similar project carried out in South America, before Struve's work was done. A similar project, with similar aims, to determine the size and shape of the earth, done by a French and Spanish team almost a hundred years before Struve. The book is called The Mapmaker's Wife: A True Tale of Love, Murder, and Survival in the Amazon and weaves the story of the mathematicians' quest with some stunning personal stories. I read it while we lived in Ecuador. I highly recommend it.

struve sextant Tartu University Estonia
A sextant thought to have been used by Struve in his work setting the geodesic arc which now bears his name.
struve telescope tartu
One of the telescopes built and used by Struve for his astronomy work.
struve monument tartu
The monument to Struve, outside his old observatory.

The Observatory and marker of the Struve Geodetic Arc are a UNESCO World Heritage site in Estonia.

You can help yourself get ready for your own travels by reading our Get Started Planning Your Trip Now page.

You can see (and buy prints) of most of our travel photos in one place on this page.

We love traveling–with the right gear. We've gathered a lot of the stuff we use to make travel more pleasant and efficient all on one page. Shop our Travel Past 50 Amazon page to find our favorite gear. If you purchase something from the store, Travel Past 50, as an Amazon affiliate, may receive a small commission at no extra charge to you. Thanks.

We never leave home without our travel insurance. Nor should you. Search for the travel insurance from Allianz that best meets your needs, whether it be an annual plan or a single trip.

Note: This post and other posts on may contain paid or affiliate advertising links.

Travel Planning Resources

Looking to book your next trip? Use these resources that are tried and tested by us.

Be sure to start with our Resources Page where we highlight all the great travel companies and products that we trust.

Travel Accessories: Check out our list of all the accessories we carry to make getting there and being there a lot easier.

Credit Cards: Find the best travel card for you at

Flights: Start finding the very best flight deals by subscribing to Thrifty Traveler.

Book your Hotel: Find the best prices on hotels with

Find Apartment Rentals: Find the cheapest prices on apartment rentals with VRBO.

Travel Insurance: Don't leave home without it. We recommend Allianz Travel Insurance.

See all of the gear and books we like in one place on our Amazon shop.

2 thoughts on “Struve Geodetic Arc, Tartu University, Estonia”

  1. Tom, We have been trying to hit one of the Struve Geodetic Arcs, but they are always so far away! Maybe Tartu, when we go to Estonia. As teachers, we also really love the scientific World Heritage Sites, but really we love them all!

    • Of all the Struve sites, this one is probably the best. The observatory itself, which is now an historic museum is very interesting. Many of Struve’s instruments are on display. My understanding is that most of the Struve sites are just markers on the ground. This one has lots to offer.


Leave a Comment

If you liked this post, please share it.