A classic sea-cavern disco near Positano
Imagine a 1960s disco, only one that is installed in a sea cavern complete with a glass floor for viewing the fishies—fishermen sometimes come to dredge the holes while the party's going on—très avant-garde chic.
That's L'Africana, a storied stalwart of the Italian glitterati nightlife scene for more than 50 years, hidden by the sea about a mile outside of Praiano.
Note that you pay the cover charge not when entering, but when leaving the club. They give you a card when you come in, which includes your first drink and the nighly cover (varies from €15 ($18) to €40 ($47)); you use this to "buy" drinks from the bar, and then settle up at the front cash desk just before leaving.
There are three ways to arrive at L'Africana: by following the path from Praiano, by riding an elevator down from the Amalfi Drive itself, or (most fashionably) aboard one of the nightclub's chartered boats (call ahead; they usually leave around 11:30pm from the Pontile Lucibello dock at Spiaggia Grande, returning to Positano at 3am).