A riwaq often serves as the transition space between interior and outdoor spaces. As portico or arcade structure, it provides shade and adjustment to sunlight in hot climates, and cover from rain in any locale.
Arcade
As an arcade element the structure is often found surrounding and defining the courtyards (sahn) of mosques and madrasas, and used for covered circulation, meeting and rest, and ritual circumambulation. The arcade element is also found along principal walkways of larger bazaars.