Erdeven hosts the Kerzerho alignments, the second largest megalithic site in Brittany after Carnac. Dating to the Neolithic period (5000-2000 BC), the site originally featured over 1,100 menhirs across 11 rows spanning 2 km. Today around 195 stones survive in 5 rows, including the "giants of Erdeven" reaching 6 metres tall and weighing up to 40 tonnes. The menhirs were re-erected in 1884 by Felix Gaillard after French state acquisition, and the site is classified as a historic monument and part of the UNESCO World Heritage application for Morbihan's megalithic landscapes.
Erdeven

| Type | Megalithic stones |
|---|---|
| Period | 4500 - 3000 BC |
| Country | France |
| Coordinates | 47.6334° N, 3.1666° W |
France