Raigad District, Maharashtra
Coordinates18°42′20″N 72°50′29″E / 18.705531°N 72.841281°E / 18.705531; 72.841281
Site information
OwnerGovernment of India
Controlled bySiddis
Open to
the public
Site history
Built1680 (1680)
Built bySiddis

Underi (also called Jaidurg) is a fortified island near the mouth of Mumbai harbour south of Prong's Lighthouse. It is a companion fort to Khanderi and currently lies in Raigad district, Maharashtra. These islands of Khanderi and Underi served as one of the landmarks for ships entering Mumbai harbour.[1] Underi is smaller than Khanderi.

The fortification was built by Kahim of the Siddis[2] in 1680 CE. [3]


  1. ^ Gazetteer of the Bombay Presidency. Govt Central Press. 1904. pp. 395–396. Retrieved 19 March 2009. underi.
  2. ^ "Underi, The Gazetteers Department". Government of Maharashtra. Retrieved 19 March 2009.
  3. ^ "Friends of Forts". Archived from the original on 7 December 2008. Retrieved 1 February 2009.