Claim: Strömsborg is a small islet in Sweden named after Strömmen ("The Stream") and the merchant Berge Olofson Ström who bought the island in 1740.
Evidence: Strömsborg (Swedish for '"Stream's castle"') is a small islet in central Stockholm, Sweden, located north of Stadsholmen, and west of Helgeandsholmen, between the bridges Centralbron, a motorway passing through central Stockholm, and Vasabron. Whenever the small island received its present name, it must have been in reference both to Strömmen ("The Stream"), the stream surrounding it, and to the merchant "Ström" and his building with the appearance of a castle (Ströms-borg, "Stream's Castle"). The merchant Berge Olofson Ström bought the island in 1740, and, according to a description from 1896 (G. Nordensvan), ten years later he had a stone house ("suitable in size") surrounded by lime trees built on the island.