Strömma Kanalbolaget (tel. 08/587-140-00; www.strommakanalbolaget.se) offers a guided cruise in English through the canals and bays to Sandhamn. Tours depart from June to August at 10am and last 8 hours. The "Canal Cruise to Sandhamn" costs 275SEK ($55/£28); children under 12 pay half fare. The company also offers the "Thousand Island Cruise" through the Stockholm archipelago. From July to August 13, the cruise costs 995SEK ($199/£100) and includes lunch and a two-course dinner. Children under 12 enjoy the same deal for half price.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.