Karimunjawa Islands

Karimunjawa is a group of twenty-seven islands about eighty kilometres north of Jepara in the Java Sea, gazetted as a marine national park covering some eleven hundred square kilometres of water, reef, seagrass and mangrove. Five islands are inhabited; the rest are empty, and the main one has a town, guesthouses and a road network. Snorkelling and diving are the point, over fringing reef and around wrecks, with a mangrove boardwalk and a hilltop viewpoint on the main island. Two things are worth knowing. The shark pens - captive reef sharks in enclosures visitors swim with - are a welfare issue that has drawn criticism. And the park has been under pressure from unlicensed shrimp ponds along the coast, a conflict that led to the criminal prosecution of local environmental campaigners.

What you actually see

• A marine national park - twenty-seven islands with reef, seagrass and mangrove.
• Reef and wreck diving - the main activity, from the inhabited main island.
• Mangrove boardwalks - the trail through the protected mangrove belt.
• Empty outer islands - only five of the group are inhabited at all.

When to go

April to October; boats stop in rough weather. Three days.

Honest expectations

Ferries are cancelled by weather and can strand you for days - build in slack. The shark pens are a welfare problem, not an attraction. Coral condition varies and some sites are damaged.

Nearby

Jepara is the mainland port; Semarang is the nearest city.