Omiš' enviable location lends itself to plenty of activities. The most gentle option is a cruise up the river canyon to pretty Radmanove Mlinice (Radman's Mills; around 100KN). Small boats line up alongside the bridge and depart when full. Hiking, rafting and zip-lining are also popular.
Rafting on the Cetina River
The Cetina is the longest river in Central Dalmatia, stretching 105km from the eponymous village. It flows through the Dinara mountains, through the fields around Sinj and gathers steam until it pours into a power plant near Nova Sela. It's an extraordinarily scenic journey, as the limpid blue river is bordered by high rocky walls, thick with vegetation. Rafting is possible upstream from Omiš from spring to autumn, but the rapids can become quite fast after heavy rains. Summer is best for inexperienced rafters.
Rafting operators tout their trips from the riverside on the old-town side of the Omiš bridge. The better operators charge upwards of 200KN. Some are cheaper, but they're not as good.