The Mare and Foal

On the north side of the present military way, between the 33rd and 34th milestone, two unhewn blocks, one of basalt, about 6 feet high - the other lower, and of sandstone, stand very conspicuously on a ridge of ground which has been artificially heightened for a small distance around them. They are now called the Mare and Foal; but on Armstrong's map, which was published in 1769, "The Three Stones."