The neighbourhood of Viterbo is particularly rich in antiquities. It was not usual with the Etruscans to build on the summits of lofty mountains, or even on the higher slopes—therefore no remains are found on the Ciminian itself—but all along its base stood city after city, now for the most part in utter desolation, yet whose pristine magnificence can be traced in the sepulchres around them. The vast plain, also, north of the Ciminian, now in great part uncultivated, and throughout most thinly inhabited, is covered with vestiges of long extinct civilisation.

Five miles north of Viterbo, on the left of the road to Monte Fiascone, and near the Ponte Fontanile, is a remarkable assemblage of ruins, commonly called Le Casacce del Bacucco. One is an edifice of two stories, by some thought a temple of Serapis, most probably because they fancied they could trace a corruption of this word in its name, Bagni delle Serpi. It is more vulgarly called La Lettighetta, or the Warming-pan. Then there are several quadrilateral buildings, evidently baths; one retaining traces of some magnificence, being surmounted by an octagon which originally supported a cupola. From the character of these ruins, and the abundance of thermal springs in this district, it has been with great probability supposed that this is the site of the Aquæ Passeris of antiquity.