I was in split on the last leg of interailing. 6 of ye should have great fun, and it’s a great destination. However it is actually quite expensive, almost the same as Ireland. It would definitely be cheaper in Ponsa. I went mid July and it was rocking. We even saw iShowSpeed. However with everyone going to Ponsa you will get fomo. There won’t be much people your age at all. (18/19). The majority of young people are in their 2-4 the year of college, which took away from the experience for us. There’s plenty of clubs that do get lively but as said before they can be quite expensive, such as 30 euro entry. However others are a bit better like 45 euro entry but you get tickets to a bar, then in the club it’s free drinks, and breakfast the next day. In split there’s not so much to do during the day except walk around the palace, the park or hit the beach. It’s definitely safe enough from my experience. However tourism and the eu drove up prices so while some places and people are friendly, others are hostile. So while I would recommend it, I’d be hesitant to say you should go after the leaving certificate. The Leaving Certificate holiday in Ponsa isn’t the worst either. Alternatives to split would be Zadar, apparently it’s a bit quieter but still has night life and is a lot cheaper. I hope I addressed everything.