Nooshabad (Noushabad) is a city in 8 km north of Kashan, laid next to central Iran desert. The underground city is a handmade complex, spread under the city of Noushabad in thousands of sq. meters, in depth of 4 to 18 meters. The city consists of many labyrinthic corridors, rooms and wells. The history of the complex backs to pre-Islamic era, More than 1500 years ago and was mainly used for sheltering and defense purposes, extended up to recent centuries. Entrances to the city were from population concentration points like water reservoirs, markets, fortress and also some individual houses. There are many spaces within the city, each consist of interconnected, 180 cm height rooms for temporary settlement connecting through angled corridors (preventing direct sight), toilets, supply stocks and guarding place. Lighting was provided by fat burning lamps. The city was built in 3 stories, each apart 3 to 5 meters in depth connecting via some narrow manholes. The architecture of the stories dictates upward movement providing maximum protection against invaders. Delaying any enemy penetration was performed by anticipating some physical obstacles and traps, in conjunction with darkness. Natural air conditioning and water supply of the city are among its ancient engineering wonders. At the moment visitors can enter the city from two entrances both opened adjacent to two old water reservoirs. All the photos are taken on hand, no flash.