Teenage holidays?

[jinkers]

Hello- I'm looking for some suggestions for my 17 year old daughter and friend, who want to have a post-exam holiday next June, somewhere in Europe. They are keen to avoid too much Magaluf/ Ayia Nappa excess as they're a bit shy, but do want a bit of nightlife and a beach, and ideally someplace they'd feel safe. Any suggestions would be gratefully received! Sorry it's a bit vague....

Their ages (under 18) might restrict them a bit in relation to things like self catering places as they will have a minimum age. also need to be v v careful about drinking if they are under 18 because some places are strict. had they thought about inter railing across europe and then can stop off for different things on the way. cephalonia is good for both chilled and night life. also enjoyed cyprus in those far off younger days/....

Thanks for the tips- hadn't thought about the self catering issue with their ages. Will look into Cephalonia and Cyprus.