It takes roughly an hour to drive from Khiva to Biruniy and a further hour to get to Ayaz

The remains of a residential area just south of the ruins of the palace at Ayaz qala 2.
From Nerazik, E. E., and Bulgakov, P. G., History and Culture of Khwarizm, History of the Civilizations of Central Asia, Volume 3, UNESCO, 1996.

It also seems that Ayaz qala 2 stood in the centre of a small rural agricultural community since there are traces of many residential buildings surrounding the foot of the conical hill on which it sits. It is possible that Ayaz qala 2 continued to be used up until the Mongol invasion in the early 13th century. 

Ayaz qala 2 was used as a backdrop for a Central Asian movie about Chinggis Khan. Amazingly the film crew were permitted to repair some of the walls and to rebuild the entry gate prior to filming. 

Ayaz qala 1 and 2 are best photographed at sunset.