Visited this place in august 2014 in monsoon.
This was my first trek.Had an awesome experience.Karnala fort 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.
Get down at Panvel and take an Auto Ricksaw which will take you to this place. You will have to take entry pass. Beware the security staff will check your bag and note down how many biscuits, water bottles etc. you have and while return again you will be checked and if they found that you have thrown a biscuit wrapper or empty botte somewhere you will be fined. Inside you will find different different ways and you will have to decide where you want to go. A one day picnic is suitable for this place.