The Gällsta Runestones from the 11th century commemorate four generations of the same family in Viking Age Sweden. There are three runestones (U 229, U 231 and U 232) and a raised stone which is only inscribed with a cross (U 230). The runestones are located at the northern outskirts of Stockholm, just northwest of the lake Vallentunasjön, around which is found the world's greatest concentration of runestones. All the Gällsta Runestones are attributed to Öpir, the most productive of all the old runemasters.