The covered avenues are often built beneath masses of earth, and the inner rooms became regular hypogea, These hypogea, or subterranean chambers, are very common near Paris, and we may mention amongst many others those of Meudon, Argenteuil, Conflans-Sainte-Honorine, Marly, Chamant, La Justice, and Compans. The tombs of Denmark, the _Gang Graben_ of Nilsson, show an arrangement somewhat similar, a vast subterranean chamber being reached by a passage ending in a small stone cist. The tumulus of Dissignac, near Saint-Nazaire (Fig. 60), shows this strange arrangement of two galleries running parallel with each other at a distance of about eighteen feet. The walls and ceilings are made of slab, anti the interstices are filled in with flints. These galleries are some thirty feet long, and their height insensibly increases from about three to nine feet. [Illustration: 60.] Covered avenue of Dissignac (Loire-Inférieur); view of the chamber at the end of the north gallery. We must also mention the Cueva de Mengal, near the village of Antequera, in the province of Malaga (Fig. 61) Twenty stones form the walls of the crypt, five blocks of remarkable size serve as a roof, and to ensure solidity three pillars are set upright inside of the junction of the roof blocks. The crypt is some seventy-nine feet long, its greatest width is about nineteen feet, and its height varies from about eight to nine feet. The length of the Pastora room, near Seville is about eighty-seven feet, but its height is not to be compared with that of the one at Antequera. The square crypt at Pastora is very interesting. One of the roof stones having been broken, it has been strengthened by the addition of an inside pillar.17 [Illustration: 61.] Covered avenue near Antequera. At Gavr’innis, the length of the passage leading to the crypt exceeds forty-two feet (Fig. 62), and the Long Barrow of West Kennet is more than seventy-three feet long by a width in some parts exceeding thirty-two feet. In the Long Barrows of Littleton, Nempnitt, and Uley, the crypt is reached by an avenue, the entrance of which is closed by a trilithon, and a similar arrangement is met with in many megalithic monuments of Scania. The sepulchral chambers of oval shape, such as that met with in the island of Moen, were surmounted by a tumulus some 100 yds. in circumference; twelve unhewn stones formed the walls, and five large blocks the roof. In removing the earth from the Moen tomb, the bones of several human individuals were found; and a skeleton, doubtless that of the chief, lay stretched out in the middle of the chamber, whilst the bones of the others had evidently been ranged against the walls either in a sitting or crouching position. With the bones were found a flint hatchet, which appeared never to have been used, a number of balls of amber, and several vases of different shapes. [Illustration: 62.] Ground plan of the Gavr’innis monument.