Karnala bird sanctuary is a small forest in Raigad district of Maharashtra.
The fort lies within the bird sanctuary perimeter. Its a thickly forested hilly region. The Karnala fort pinnacle can never be missed from Mumbai-Goa highway due to it's peculiar Thumbs-Up structure. The following image would make it clear:
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Route:
Panvel -> Karnala Bird Sanctuary = 12 KM