Today I have visited Stonehenge, one of the most outstanding prehistoric monuments. I spent two hours (by bus) to arrive there, and I can say this journey is paid off. The place is really excellent for astronomy purposes, because it has a perfect horizon, without hills or mountains disturbing the skyline. You can see only some of the original stones it contained, just the stones which are still there.
They made this to establish and study the seasons. There are stones marking the position of the Sun in the different season. Nobody really knows how those humans did it, how they brought the stones from far mountains, how they put them in perfect positions. I know there are recent studies (made with the help of computers) which show an incredible variety of lines between the stones, pointing to different (and exact) positions on the horizon. Anyway it’s a really enjoyable journey for an astronomy hobbist (or ex-hobbist, as I am).
And I must say I was lucky in my visit, because some people next to the place were blowing a big balloon, and they offered a trip for free. So I took some pictures of Stonehenge from a bird’s view! Excellent!
Sometime ago I read in a humour novel about computers that said “the first computer made by humans was Stonehenge”, because (roughly speaking) it “calculates” something. So, for me, this journey wasn’t only a visit to a prehistoric monument and an astronomical place, but also a computer science and engineering construction!