Complex sentence: The closed hall which has no windows and connects to the sanctum via a vestibule (called "sukhanasi") which also as a tower (also called "sukhanasi") that looks like a low protrusion of the main tower over the shrine.
Split into simpler sentences: The closed hall which has no windows and connects to the sanctum via a vestibule (called "sukhanasi"). The vestibule also as a tower (also called "sukhanasi") that looks like a low protrusion of the main tower over the shrine.