Tunnelling in IRAN has long history started from pre-Islamic era to today:
EXAMPLE OF YESTERDAY:
Noosh Abad underground city adjoining the Central Desert of Iran consists of many labyrinthic corridors, rooms and wells. The history of the complex backs to pre-Islamic era, at least since 1500 year ago, in Sassanian period (224-637 CE), and was mainly used for sheltering and defense purposes extended up to recent centuries. The handmade complex spread under the city in thousands of sq. meters, in depth of 4 to 18 meters.
EXAMPLE OF TODAY:
Isfahan city is the capital of Isfahan province in Iran, located about 340 kilometers (211 miles) south of Tehran.
Isfahan metro is under construction and will include 2 lines with 43 km (27 mi) length. The first line of that is planned to be operated by end of 2014 with 21 km (13 mi) length and 20 stations. The twin line was executed by cut and cover, roadheader and EPB Tunnel Boring Machines.