The Cassero is the monument which officially marks the birth of Castel San Pietro in 1199.
On an internal arcade of the building you can see a marble plaque with the following latin inscription (Italian version)
"Correndo gli anni mille e duecento,
quando Rolando detto di nome Parmense,
cultore di giustizia e vero amator di pace,
Bologna governò osservando i legali diritti,
allora comandò, anche desiderando di tener la pace,
che questo Castello si facesse nel contado Bolognese
per rendere il cammino sicuro ai viandanti
e per fugare col timor delle pene i malfattori.
The new rampart was firstly built in wood and then it was transformed again and again according to the armies needs which, decade after decade, century after century, have conquered it and used it as the main rampart against enemies.
The Cassero (from Arabic "qasr", castle, roman castrum) is at present a massive building, embellished by swallow-tiled merlons.
The main door was to the right of the current one, as it is testified by the chain imposts of a drawbridge.
It was rearranged several times and covered by a roof. In 1830 it was transformed in a theatre and then it was restored according to the previous structure during the years after the First World War.
By now the Cassero has a multiple theatre, with nearly 200 seats. Musical and theatrical performances, conferences and artistic exhibitions take place there.
In the upper part of the Cassero is the clock tower whose first documents date back to 1300.
In 1784 a clock and the bells were placed on the tower.
From 1635 to 1920 (when this building was given to the Municipality) it belonged to Malvasia family.