Stigberget was once called The Gallows Hill and not without a reason. In the 16th and 17th centuries it was the town execution site, and can be seen on many old paintings and maps. It had a foundation of stone, built like a low, round tower. There were three stone pillars on top of the foundation, and the ropes were attached to wooden beams between them. The gallows stood at the hill’s highest point so that the executed would be visible from all over the town. As many as ten people could be hanged at the same time, and the corpses would dangle there for a long time as a deterrent for others.

In the late 17th century the gallows moved to Hammarbyhöjden and the place lost its terrifying atmosphere. In the beginning of the 20th century Stockholm Navigation School was built here on the hill. On the 25 meter high tower there is a signal mast with a so-called time ball. It is a mechanical device that indicates correct time for the vessels in the harbour. The ball is a spherical basket made of sheet metal. It lifts up and then falls for five minutes. When it is back down the time is exactly 12:00 GMT and the on-board chronometer on a ship could be corrected after that. The time ball is still in operation today.

Since 1982 the building has housed Ersta Sköndal high school.