Few landmarks in Groningen are as emblematic as Martini Tower, or 'the old grey one' as the locals call it, which proudly signals its presence from afar, guiding visitors to both the church and the main market square 'Grote Markt.' The current structure was built in the 15th century and stretches almost 100 metres into the skyline, offering panoramic vistas for those who climb all 260 steps.

In 1996, American artist James Turrell designed the Celestial Vault to showcase the sky in all its glory using an innovative astronomical optical illusion. In the centre of this grassy artificial crater, there is a stone bench on which visitors can lie to observe the sky as a curved dome, emphasising the way light affects how we perceive things and inviting those willing to challenge their own perceptions.

The Struve Geodetic Arc is a chain of survey triangulation points that stretch from Hammerfest in Norway all the way to the Black Sea. The imaginary lines go through ten countries and over 2,820 kilometres. Carried out between 1816 and 1855 by the astronomer Friedrich Georg Wilhelm Struve, this survey represented the first accurate measuring of a long segment of a meridian, helping establish the exact size and shape of the planet. Sweden has seven measurement points and four of them are on the World Heritage List (on the mountains Tynnyrilaki, Jupukka, Pullinki, and Perävaara). The mountaintop unveils an expansive view.