The name of the square comes from the mispronunciation of S. Ubaldo. It has a characteristic truncated bell tower whereas the church no longer esists.

The church was built in the early ninth century by the will of the families Giusto and Tron and initially entitled to Sant'Agata. Burned and rebuilt, was eventually entitles to San Ubaldo (misspelled San Boldo), given its proximity to a hospital built by the DeMatteo family by the end of 1300. Like many other churches it was destroyed to make room for housing during the Napoleonic period and the flat top bell tower is all that remains.
In the square there is one of the classic well heads

 and one of the seven crooked bridges of the city is located nearby