Do we need to book the tour around the island and a visit to the blue grotto ahead of time or can we just purchase when we get there - it will be may 27
Last week of May will have heavy tourist volume. Note that the Blue Grotto (a notorious time-sucker, we skipped it ... ) requires on-water transfer to the tiny boat that actually enters the grotto - so it can be cancelled for high winds and waves. Also a second tipping opportunity. Ferry to Capri will be crowded as well. Are you coming from Sorrento, Naples, or elsewhere?
Coming from sorrento
I bought the boat tour around the island right there in the marina. It takes about one hour to go around. About 45 minutes in, the boat stopped at the Blue Grotto for about 20/30 minutes so those that wanted to go into the grotto could go in. You get in a small rowboat and a guy takes you in for about 5 minutes. So the total trip is about 90 minutes.