The city centre on Trossö island is compact and easily walkable — the main sights on Stortorget, the Admiralty Church, Björkholmen, and the ferry terminal are all within 20 minutes of each other on foot. The naval museum at Marinmuseum is a ten-minute walk east of the square.
The archipelago is reached by free passenger ferries from the terminal near Fisktorget. Ferries run frequently in summer to the main islands — check the Karlskrona municipality website for current timetables. Bicycles can be taken on most ferries, and hiring a bike makes island-hopping significantly easier.
Local buses serve the mainland areas around the city, and there are bus connections to the ferry port at Verkö. Taxis are available but rarely necessary for sightseeing within the city. The streets of the centre are mostly flat and easy going, though the granite cobblestones of Björkholmen and Stortorget can be slippery in wet weather.