Claim: Strömsborg is a small islet which is a part of Gamla stan, the old town of Stockholm in Sweden that was 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. Strömsborg is part of Gamla stan, the old town of Stockholm and is connected to the rest of the world by the bridge Strömsborgsbron leading over to 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").