Portuguese mariners exploring the north Konkan Coast, discovered the Arab Sultanate of Khambat or Cambay, building or renovating or expanding the fort in the early 1400s and attacked it in a failed effort to seize it. Later, after more systematic efforts, the Sultanate of Cambay ceded the fort to Portugal by the Treaty of Saint Matthew signed on the Portuguese brig Sao Matteus anchored in the Bhayander Creek or Vasai Harbor. Under Portugal, the fort was the Northern Court or "Corte da Norte," second only to the City of Goa, functioning as the headquarters of the Captain of the North. As such it was the capital of Portuguese possessions on the coast north of Goa, over places such as Chaul-Revdanda, Karanja Island, the Bombay Archipelago, Bandra Island, Juhu Island, Salsette Island including the City of Thane, Dharavi Island, the Vasai archipelago itself, Daman, Diu, and other Portuguese holdings extending up the coasts uptil Pakistan, Oman, the UAE, Iran, and other parts of the Persian Gulf. The ethnic community locally known in the Bombay region as the "East Indians" (sic) were called "Norteiro" (Northernmen) after the Court of the North functioning out of the fort. Statue of Chimaji Appa at the Fort One of the few standing structures Vasai fort building2.jpg In the 18th century, the fort was attacked by the Maratha army under Peshwa Baji Rao's brother Chimaji Appa, and fell in 1739 after a three-year-long campaign. The English shortly after took over the territory from the Marathas as the price for supporting one faction of the Marathas against another.The ramparts overlook what is alternatively called the Vasai Creek and the Bhayander Creek and are almost complete, though overgrown by vegetation. Several watch-towers still stand, with safe staircases leading up. The Portuguese buildings inside the fort are in ruins, although there are enough standing walls to give a good idea of the floor plans of these structures. Some have well-preserved façades. In particular, many of the arches have weathered the years remarkably well. They are usually decorated with carved stones, some weathered beyond recognition, others still displaying sharp chisel marks. Three chapels inside the fort are still recognisable. They have façades typical of 17th century Portuguese churches. The southernmost of these has a well preserved barrel-vaulted ceiling. The fort is often used for shooting Bollywood film scenes. The films shot here include Josh, Khamoshi, and Ram Gopal Verma's Aag. Besides all the structures one should not miss observing the nature that has taken over much of the fort. It is a great place to observe butterflies, birds, plants and reptiles. The Archaeological Survey of India has started restoration work of the fort, although the quality of the work has been severely criticized by "conservation activists".