Not only is Carnac a fantastic open-air museum that appeals to culture vultures, but it's also a superb playground for beachy types. Grande Plage is Carnac's longest and most popular beach and is excellent for sunbathing – it's a 2km-long stretch of white sand 2km south of Carnac-Ville. To the west, Plage de Légenèse and Plage de St-Colomban are smaller and quieter. St-Colomban appeals to windsurfers.

Feature: Carnac's Mysterious Megaliths

Two perplexing questions arise from the Brittany's neolithic menhirs, dolmens, cromlechs, tumuli and cairns. Just how did the original constructors hew, then haul, these blocks (the heaviest weighs 300 tonnes), millennia before the wheel and the mechanical engine reached Brittany? And why?

Theories and hypotheses abound, but common consensus is that they served some kind of sacred purpose – a spiritual impulse that has motivated so much monument-building by humankind.

Just north of Carnac is a vast array of monoliths arranged in several distinct alignments, all visible from the road, though fenced for controlled admission. There are also several spectacular sites around the Golfe du Morbihan, including Cairn de Gavrinis, Locmariaquer Megaliths and Cairn de Petit Mont.

The main information point for the Carnac alignments is the Maison des Mégalithes, which explores the history of the site and has a rooftop viewpoint overlooking the alignements. Due to severe erosion, the sites are fenced off to allow the vegetation to regenerate, and certain areas are accessible only by guided tour. The Maison can organise one-hour guided visit, several times daily in French and weekly in English during the summer. (Call to confirm times.) From March to October, selected parts are open for visitors to wander freely – ask the Maison for maps.

The best way to appreciate the stones' sheer numbers is to walk or cycle between the Ménec and Kerlescan groups, with menhirs almost continuously in view. Between June and September, seven buses a day run between the two sites, as well as Carnac-Ville and Carnac-Plage. The Carnac-Ville tourist office has an excellent map of all the nearby sites.

On the other side of the road from the Maison des Mégalithes, the largest menhir field – with 1099 stones – is the Alignements du Ménec, 1km north of Carnac-Ville. From here, the D196 heads northeast for about 1.5km to the equally impressive Alignements de Kermario (parts of which are open year-round). Climb the stone Moulin de Kermaux midway along the site to view the alignment from above.

The massive burial mound of a neolithic chieftain dating from 3800 BC, the astonishing Tumulus de Kercado lies just east of Kermario and 500m to the south of the D196; look for the signs. Deposit your fee (€1) in an honour box at the entry hut that you walk through to reach the site. You can walk through the passageway (there's a light switch) and stand up within the chamber at the heart of the tumulus. About 300m east of the Kercado turnoff along the D196 lies the parking area for the Géant du Manio. There's a parking area just off the road next to an equestrian centre, then a 15-minute walk brings you to vast rock amid the pines, the highest menhir in the complex. Just before you reach it, you will see the rectangular arrangement of stones known as the Quadrilatère du Manio.

The easternmost of the major groups is the Alignements de Kerlescan, a smaller grouping also accessible in winter.

Tumulus St-Michel, 400m northeast of the Carnac-Ville tourist office, and accessed off the D781 at the end of rue du Tumulus, is a gigantic burial mound with a church on top. It dates back to at least 5000 BC and offers sweeping views (exterior access only).

Be sure to visit the Musée de Préhistoire in Carnac-Ville to see the incredible neolithic artefacts found throughout the region.