Cloister

open space surrounded by covered walks or open galleries in monasteries

A Cloister is a term in architecture. It describes a structure which is usually found in monasteries, churches and old colleges. It is a rectangular open space surrounded by covered walks or open galleries. It has open arcades on the inner side, running along the walls of buildings and forming a quadrangle.

The cloister of a ruined abbey in Utrecht.
Cloister of Maius College in Kraków.
The cloister of Quwwat ul-Islam Mosque. It is part of the World Heritage site Qutb Minar in Delhi.