These walls and ramparts are what is left here of Kvarnholmen's inner fortifications. In the early 1800s, when much of the walls were demolished, they wanted to turn the remains into green trails, and rows of linden trees were planted along the dike. Then a "hole" was made in the dike, on which today's Olof Palme's street was built. In this way, Larmtorget gained a completely new status as an "arrival square".
If you have the chance, go up the stairs behind the theater, or up the stairs on the dike, and follow the trail past the station — you will also pass the Union Monument on your left on the way to point 18.