Does anyone know if you can see the grotto if you arrive by bus rather than boat? Would really like to do some hiking that will put us at the grotto when done and was curious if you could go down and catch a boat inside. Thanks
You can walk to near the entrance (I think there is a bus too), but you still need to queue up to get on the little boats because you can get inside only on those little boats (and you have to stay down because the hole to enter it is very low). I don't think they allow people to swim to it, even after hours.
The admission fee is 13 euro.
Or just enjoy it on YouTube:
http://www.capri.it/it/s/la-grotta-azzurra-2
Believe everything Roberto stated is correct and would be shocked if you could swim in, as the whole thing is a big money maker and the captains of the small boats request gratuities here.
Be aware they close this attraction if the seas are only a couple of feet swells as the opening is so small, so many times throughout the year you cannot go to the Blue Grotto