The Cassero Senese looks like a low but imposing tower with a rectangular section, externally clad in travertine; the sixteenth-century covered top terrace, on the other hand, has a brick parapet.
On the side facing the outside of the walls, along the ring road, the black and white coat of arms of Siena and the characteristic double arch are worthy of note, where the pointed arch clearly stands out above the lowered round one; the finishes are in travertine and black marble. The double door that opens was the ancient Porta di Santa Lucia, which was an access point to the historic center along the medieval walls.
It is mainly used for the display of exhibitions of an artistic and photographic nature such as the one held annually for the Resistant Festival on the occasion of April 25th.
source: Wikipedia