morro do leme was first fortified by the marquis of lavradio between 1776 and 1799. fort vigia, as it was called then, was constructed on the site of the hill to monitor shipping traffic entering and leaving the bay, and to keep watch for any invading fleets.

the current structure (originally known as fort leme) was erected in 1895 and later equipped with powerful cannons as part of the defense system for the port of rio de janeiro.

the locale also has some interesting and eccentric moments in its history - tiradentes, hero of brazilian independence, served in the fort before his execution in 1792, and in 1943 the aforementioned cannons were used to bombard a group of nazi submarines which were later discovered to be whales.