"The tower of the Asinelli rises the height of about 350 feet, and is
said to be three feet and a half out of the perpendicular. The
adventurous traveller may ascend to the top by a laborious staircase of
500 steps. Those steps were trod by the late amiable and excellent Sir
James Edward Smith, who has described the view presented at the summit.
'The day was unfavourable for a view; but we could well distinguish
Imola, Ferrara and Modena, as well as the hills about Verona, Mount
Baldus, &c., seeming to rise abruptly from the dead flat which extends
on three sides of Bologna. On the south are some very pleasant hills
stuck with villas.' The Garisenda tower, erected probably by the family
of the Garidendi, is about 130 feet in height, and inclines as much as
eight feet from the perpendicular. It has been conjectured that these
towers were originally constructed as they now appear; but it is
difficult to give credit to such a supposition.

"According to Montfaucon, the celebrated antiquary, the leaning of these
towers has been occasioned by the sinking of the earth. 'We several
times observed the tower called Asinelli, and the other near it, named
Garisenda. The latter of them stoops so much that a perpendicular, let
fall from the top, will be seven feet from the bottom of it; and, as
appears upon examination, when this tower bowed, a great part of it went
to ruin, because the ground that side that inclined stood on was not so
firm as the other, which may be said of all other towers that lean so;
for besides these two here mentioned, the tower for the bells of St.
Mary Zobenica, at Venice, leans considerably to one side. So also at
Ravenna, I took notice of another stooping tower occasioned by the
ground on that side giving way a little. In the way from Ferrara to
Venice, where the soil is marshy, we see a structure of great antiquity