Karnala fort also called Funnel Hill is a hill fort in Raigad district about 10 km from Panvel city. Currently it is a protected place lying within the Karnala Bird Sanctuary. It was a fort of strategic importance as it overlooked the Bor pass which connected the Konkan coast to the interior of Maharashtra (Vidharba) and was the main trade route between these areas.
Karnala fort actually consists of two forts one at a higher level and other lower. At the centre of the higher level is a 125 feet high basalt pillar. It is also called Pandu's tower. This structure was used as watchtower when the fort was occupied however now it is in a ruined condition. The presence of bee hives also makes it difficult to climb and have resulted in at least one casualty in recent times. There is a water cistern which provides fresh water all year long. From the top the forts of Prabalgad and Rajmachi are clearly visible.
The fort has two inscriptions one in Marathi and the other in Persian. The Marathi inscription which has no date is seen on the lower gate on the inner side. Its words are indecipherable. The Persian writing is on upper gate reads "Syed Nuruddin Muhammad Khan, Hijri, 1147 AH (1735 CE) and probably dates from the Mughal occupation of the fort.