Its location in a forested area adds to the mysterious and ancient atmosphere of the site, and, its neolithic era. Dolmen de Bagneux is one of the largest dolmens in France and in Europe.
Its chamber is still in tact. Though porch suspected damaged. It’s only a little narrower on the entry side. And, almost rectangular. Made of single bottom flagstone. 4 supports on each the north and south side. 4 roof stones; and, 2 stones supporting the door. In all. 15 pieces; and, two wedging stones. Are seen.

The overall length of this dolmen is over 23 meters (75 feet) and its chamber is over 18 meters (59 feet) long.

The massive flagstones are of tertiary sandstone. The do not come very far away. A layer of these stones exist nearby. On the heights of Bournand and Terrefort. They were probably scattered on the slopes of the hill. And, pushed down. 300 meters or so. Man up.
Like many megalithic sites in Anjou. It is oriented SE.
Of the 4,500 dolmens spread out over 60 French departments. Only the Spanish dolmen in Antequera (link), near Málaga (Spain), is bigger.

The Dolmen de Bagneux, contributes to our understanding cultural and architectural practices of neolithic societies in the region. These structures are often considered archaeological treasures and are protected for historical significance. Visitors interested in history and archaeology can explore these dolmens as part of their exploration of France’s neolithic past.

Bibliography:
Site internet du Dolmen de Bagneux (https://web.archive.org/web/20130115130452/http://www.ledolmendebagneux.com/accueil.php)