The Carnac Megalithic Complex
The Carnac Megalithic Complex is a dense and extensive collection of megalithic sites situated mostly to the north of the village of Carnac. It consists of stone alignments, burial chambers, and individual standing stones. Over 3,000 stones were erected at this Neolithic site, largely around 3,300BC, with some dating back as early as 4,500BC. It is thought to be the largest collection of of standing stones in the world.
The Carnac complex can be slightly overwhelming, and it's a good idea to do some research before visiting, as there's a lot here that would be easy to miss. It also helps to have a mental image of the lay-out of the site, as this helps put things in perspective on the ground.
Access to the alignments at Carnac is now prevented by a low wire fence, due to excessive erosion caused by large numbers of tourists. However, access is still allowed out of season, but specific dates should be checked before travel.
The Alignements de Kerlescan
The Alignements de Kerlescan consists of 555 stones, arranged in alignments of 13 rows. These run to a length of around 800 metres, with the tallest stones standing as high as 4 metres.
The Alignements de Kerlescan sit at the north-eastern end of the main Carnac alignments. They're possibly the best location from which to begin when visiting Carnac. I'd advise parking here and proceeding on foot towards the south west.