On 17 May 1902 archaeologist Valerios Stais made the most celebrated find: when diving to search the area of the Antikythera wreck, he noticed that one of the pieces of rock near him had a gear wheel embedded in it. It would soon be identified as the Antikythera mechanism; originally thought to be one of the first forms of a mechanised clock, it is now considered to be the world’s oldest known analog computer.
The Antikythera mechanism is an ancient mechanical calculator designed to calculate astronomical positions. Its complexity and significance were not understood until decades after it's discovery. It is now thought to have been built about 150–100 BC. Consensus among scholars is that the mechanism was made in Greece. All the instructions of the mechanism are written in Greek.
Do certainly take along a large amount of recording equipment.
Especially when you're a large troop - or a very enthusiast couple - visiting Stonehenge, nothing is stopping you from taking along as many different recording devices as the total amount of arms can carry. Where as device X might be perfectly fitted for occasion Y, you could prefer device Z for situation N. An example: