Today I’ve visited the Stonehenge!
The Stonehenge is located in Amesbury and it’s one of the most famous monuments of the World! The first phase of the monument was built between 3000 and 2900 BC in the Neoilthic Age. In those times, Stonehenge was a typical causewayed enclosure. When we approach to the central stones, we can see that there are two kinds of different ones depending on their size. A lot of stones are very big (Sarsen stones) including the vertical ones while there are some smaller stones (blue stones) between them. They were placed in a clear astronomical alignment so in the Solstices and the Equinoxes there are some special stones which are placed like a calendar:
I’m not going to do an astronomical class here because the alignements are well known but I thonk that this monument is one of the obligatory symbols for the mathematical tourists.
You have an interesting description in the UNESCO website: link.