Just a short ferry ride (use your Ruter ticket) is a collection of islands, so you can go islandhopping in the Oslo fjord! The biggest island is Hovedøya (The Main Island), and here you get a little of everything: nature, beach, forest, cultural attractions (a 12th-century monastery and military ruins) and a café. Just remember, no camping or fires allowed – but you can still enjoy a barbecue by the beach!