The Yunak Evleri Cave Hotel, Urgup, Cappadocia, Turkey
This hotel is a combination of six cave houses with a total of 39 rooms from the 5th and 6th centuries and a 200-year-old Greek mansion.
(via Yunak Evleri Press Room)
Cave homes and a chapel in Louresse-Rochemenier, France
Ancient Cliff Houses of Guyaju, near Zhangshanying, China
This complex has 131 rooms that were carved into the mountain cliff. These multi-story homes have ventilation holes, water drainage, and heating systems.