Kyrgyzstan, Tash Rabat Valley. River and Old Caravanserai. The Caravanserai of Tash-Rabat was constructed in the 15th century, on the ancient trade route from Central Asia to China and was a resting place for merchants, ambassadors, travelers and other wanderers. It is the largest construction built of stone of the Central Asian architecture of that era. It is notable not only for it's size and building materials, but also for its special layout, based on perfect symmetry.