e of its erection is hid in
the dim traditions of the past. The traditions of the Nahua tribes,
who came at a far later date, speak of it as even then standing on the
plain. Scattered over the plain are other ruins of a somewhat different
nature from the general ruins in the valley. These may be the ruins
of works erected by the same class of people as built the mounds.
Especially is this thought to be true of ruins found on the slopes of
neighboring volcanoes.

To the south-west of Cholula are the ruins of Xochicalco, which, by
some, are pronounced to be the finest in Mexico. There are many points
of resemblance between this ruin and Tezcocingo. The meaning of the word
is "Hill of Flowers." The hill is a very regular, conical one, with a
base nearly three miles in circumference, and rises to a height above
the plain of nearly four hundred feet.<36> The hill is considered to be
entirely a natural formation; but it probably owes some of its regular
appearance to the work of man. Around the base of the hill had been dug
a wide and deep ditch. When Mr. Taylor visited the place, the side
of this moat had fallen in, in many places, and in some quite filled
up--but it was still distinctly visible.<37> The whole surface of this
hill was laid off into terraces.

Five of these terraces, paved with blocks of stone laid in mortar, and
supported by perpendicular walls of the same material, extend, in oval
form, entirely around the whole circumference of the hill, one above the
other. From the accumulation of rubbish, these terraces are not easy to
detect in all places. Probably, at one time, there was some easy means
of access from one terrace to the other, but they have disappeared--so
that now the explorer has to scramble up intervening slopes of the
terraces as best he can. It is probable that defensive works once
protected these slopes.

Mr. Mayer says: "At regular intervals, as if to buttress these
terraces, there are remains of bulwarks shaped like the bastions of a
fortification."<38> "Defense seems to have been the one object aimed
at by the builders." The top of the hill is leveled off. Some writers
represent that a wall of stone was run along the edge of the summit but
others think that the whole top of the hill had been excavated, so as
to form a sunken area, leaving a parapet along the edge. This
summit-platform measured two hundred and eighty-five feet by three
hundred and twenty-eight feet. Within this area were fo