Upstalsboom

During the Frisian freedom period, the Upstalsboom, also known as the Opstalsbam, was an assembly for emissaries of the Seven Sealands of medieval Frisia, located just outside the East Frisian town of Aurich in modern-day Germany. The origins of the Upstalsboom, including its name, are unclear, but as far back as the 8th century the meeting place was used as a burial ground for the members of important Frisian families.