Karnala Fort is situated at a height of 445 meters from sea level. It was used to keep a watch on the trade routes passing through old Panvel and Bhor Ghats, to Mumbai and Chaul ports.

This fort was ruled by the Yadav kings of Devagiri between 1248 and 1318. Later, between 1318 and 1340, it was under the Muslim rulers of Daulatabad. In those days, Karnala was the headquarter of the North Konkan district (Thane & Raigad). After this period, it was under the rule of the army of Gujarat. In the year 1540, the Ahmednagar army took it over.
The army of Gujarat, along with the Portuguese won it back. The Ahmednagar army surrounded the fort. So the Gujarat army handed over the charge of the fort to the Portuguese. The Captain of Vasai Fort invaded and drove away the Ahmednagar army. The Portuguese kept back 300 European soldiers for the protection of the fort. A treaty was signed between the Portuguese and the Nizam of Ahmednagar. The fort was handed over to the Nizam who had to pay a yearly security amount of 1050 Pounds. Shivaji Maharaj defeated the Mughals and took over the fort in 1670. Later as a part of the treaty of Purandar with Mirza Raje Jaisingh, Shivaji had to hand over the fort to the Mughals. He later won it back. After the death of Shivaji, Aurangzeb took over the fort. Around 1740 it was under the rule of the Peshwas of Pune. The British army took charge of the fort in 1803 on behalf of Bajirao II. It remained with the British post-1818. The grandfather of great freedom fighter, Vasudev Balvant Phadke, was the Killedar (Governor) of this fort till 1818.