About 40 minutes' drive north of Sinj, at the foot of the Dinara range, the river Cetina emerges from a brilliantly blue circular pool. The water is intensely cold and almost luminous when seen from above. A small Orthodox-style church, the Holy Salvation, sits beside the spring.
There is a short path around the pool and a viewpoint above it. Bring a swimsuit only if you are tough — the water is around 8°C all year.