What there is to dive
The central Dalmatian coast is wreck country. There are Second World War aircraft and freighters in divable depths around the islands off Split, plus wall dives that drop past forty metres and a few short swim-through caves. Visibility is routinely twenty metres and better outside the summer algal bloom, and there is nothing to catch you out — no current worth the name, no cold thermocline until you are deep, no tide.
If you have never dived
A try dive is a pool or shallow-bay session with an instructor and one supervised dive to about six metres. No certificate, no course, no commitment: you find out in one morning whether breathing underwater agrees with you. Most centres take children from ten. Expect around €80–100 including all the kit.
If a mask is enough, snorkelling off the Marjan shore costs nothing.
If you already dive
Bring your card and your logbook. A single guided dive from a centre boat starts around €45 with tank and weights, and about €70–80 with full equipment hire. A two-tank day out to the wrecks runs to roughly €110–140. An SSI or PADI Open Water course is around €550 and takes three to four days, which is a real chunk of a week's holiday — worth knowing before you commit to it on the first morning.
Where the boats leave from
Centres are spread between the city, Žnjan and the coast east towards Omiš. Žnjan has been a moving target while the beach was rebuilt, and at least one centre shifted its operation to Omiš for a season, so confirm the actual departure point when you book rather than assuming it is where the shopfront is.
Žnjan is the rebuilt beach strip east of the centre — see the Žnjan beach guide.
Omiš is half an hour down the coast, and the Omiš and Cetina day trip covers the town and the gorge behind it.
Things to do in Split
Boat trips and tours
Split in one day