Set on the 530 acre estate, the Cave House was built with the philosophy that the ongoing preservation of natural beauty is paramount. With its perfect blend of magnificent craftsmanship and technology, it took nearly four years to complete. Everywhere one looks, the superior design and attention to detail is obvious.
Putting you directly in touch with nature, the house boasts natural living cave walls and ceilings. By maximizing window areas along the wall facing outside, and maintaining large, open living spaces, natural sunlight floods the living area, pool room, and kitchen, bringing the outdoors inside the cave.
Link -via Grow-A-Brain
Previously at Neatorama: A cave hotel in Turkey.