The Stockholm Archipelago contains approximately 30,000 islands, skerries, and rocks stretching 80 kilometres from the city centre into the Baltic Sea. Less than one thousand are inhabited. The waterway served as a military buffer zone for centuries — granite fortifications and naval stations still punctuate the outer reaches — but today the skärgård functions as the capital's maritime recreational corridor, accessible year-round from Strandvägen and other central piers. Systematic boat service began in 1850 with coal-fired steamers connecting island communities to Stockholm's markets. By the 1920s, weekend excursion traffic had established the white-hulled waxholmsbåtar as the archipelago's signature vessels. Modern operators deploy both traditional wooden boats and high-speed RIB craft, but the route architecture remains anchored to the historic steamer network. Departures concentrate between May and September, though year-round schedules serve year-round residents on islands like Värmdö, Utö, and Sandhamn. The best archipelago boat tour Stockholm itineraries navigate the inner, middle, and outer zones. Inner routes pass Fjäderholmarna — the closest island group, reachable in twenty minutes — where rocky shores give way to pine forest and nineteenth-century boathouses. Middle archipelago stops include Vaxholm, a fortress town guarding the northern approach, and Grinda, known for its red cottages and sandy swimming coves. Outer routes push past the last permanent settlements into the open Baltic, where lighthouses mark navigation channels and grey seals haul out on wave-swept rocks. Water depth drops from 40 metres in the inner bays to over 200 metres beyond Landsort, the southernmost lighthouse. Seasonal timing shapes the experience. June brings near-constant daylight and calm water. August offers warm swimming and peak wildflower colour on the islands. October light turns sharp and low, casting long shadows across the granite, but departures thin and crossings grow rougher. Most operators suspend service between November and March, resuming when ice retreats and the archipelago sheds its winter stillness.