Hi friends,
I am resident of thane near Mumbai. As Alibag is 120 km from Mumbai, and 90 km from thane.I will give u full description about Alibag.
1) Accessibility - In Alibag you have all type of accessibility as it is near to Mumbai, so you dont have to worry,
2) local sightseeing - In Alibag you have many sightseeing near to Alibag. Near Alibag there is another beach called Varsoli the beach has less people so you can enjoy more. Varsoli beach is 3 km from Alibag. there is another beach 20 Nagao beach this beach is longest beach and u will have various accommodation facilities. and there is Kashid beach also which is 25 km away but more tourist come there to have sea bath and sunbath. Other sightseeing are the forts.
3) hotel/ accommodation- there are many hotel so there is no worry. it depends upon you at what price you want to rent a room from average people to rich people you will get hotel.
4) safety - safety wise Alibag is more preferable. you dont have to worry about that at all.