Less than a mile south of Chapultepec, and within range of its guns, is the village, or hermitage of Tacubaya, containing the palace of the archbishop, and a number of fine country seats. At the south-eastern angle of the inclosure, the Toluca road intersects the causeway, leading direct, one and a half miles, in a north-easterly course, to the gate of Belén. Here also commences the branch conducting to the San Cosmé causeway, about two miles further north. The Tacubaya causeway, the branch, from the north-eastern angle of the wall encompassing the heights of Chapultepec, and the San Cosmé causeway, from its intersection with the latter, — are double roadways, on either side of massy elevated aqueducts, supported on heavy arches and pillars, which supply the city with fresh water. The causeways are all flanked by deep ditches, and marshy grounds.
Within this exterior chain of defences, which mounted, together, over one hundred pieces of artillery, there was also an interior line scarcely less formidable. A wide and deep navigable canal, intended for drainage and for custom-house purposes, and extremely difficult, I if not impossible, to bridge in the face of an active enemy, surrounded the city throughout its greater extent. There were eight main entrances, at each of which there was a garita, or large fortified gateway, where duties were collected, as in many European towns.
On the left of the Tacubaya causeway, but a short distance in rear of the garita Belén, was the Ciudadela, or citadel, a solid rectangular work, between two and three hundred yards square. Batteries and redans were} built upon and near the causeways and garitas, and. in the intervals between them; and preparations
