Algeria has been far more completely explored, and possesses a remarkable number of megalithic monuments.  Many of the finest are situated near the town of Constantine.  Thus at Bou Nouara there is a hill about a mile in length which is a regular necropolis of dolmen-tombs.  Each grave consists of a dolmen within a circle of stones.  The blocks are all natural and completely unworked.  The circle consists of a wall of stone blocks so built as to neutralize the slope of the hill and to form a level platform for the dolmen.  Thus on the lower side there are three courses of carefully laid stones rising to about five feet, while on the upper side there is only one course.  The diameter of the circles varies from 22 to 33 feet.  In the centre of the circle lies the dolmen with its single long cover-slab.  This usually rests on two entire side-slabs, the ends being filled up either with entire slabs or with masonry of small stones.  In rare cases the side-slabs are replaced by masonry walls.  The average size of the cover-slab is 6-1/2 by 5 feet.  The dolmen itself is, of course, built directly on to the platform, and the space between it and the circle is filled up with rough stones.  The orientation of the dolmens varied considerably, but the cover-slab was never placed in such a way that its length ran up the hill-slope, probably because in moving the slab into place this would have been an awkward position.

Another equally fine site is that of Bou Merzoug, near Oulad Rahmoun, about an hour’s railway journey from Constantine.  The place is naturally adapted for a settlement as there is a spring of water there.  This spring was later utilized by the Romans to provide water for the city of Cirta.  The dolmen-graves lie in great numbers on the hill at the foot of which the spring rises, and extend down into the valley.  Each dolmen lies in the centre of a stone circle.  This last is in some cases formed by very large slabs set on edge, but more often by two or three courses of rough oblong blocks.  Many of the graves are badly damaged.  One of the finest had an outer circle about 27 feet in diameter, and an inner circle 14 feet in diameter.  Between these two a third circle, much more irregular and of small stones, could just be distinguished.  But in most cases it was impossible to make out clearly more than the one outer circle and the dolmen within it.  The dolmen itself consisted of a large slab resting on walls formed of several large blocks, the spaces between which were filled up with smaller stones.  None of the stones used were worked.  The dolmens were not oriented according to any fixed system.  M. Feraud states that the separate graves were united together by open corridors formed by double or triple rows of large stones, but no traces of such a system could be found by the later visitors to the site, Messrs. MacIver and Wilkin.