Jättegrytan i Skarpnäck

Useful Information

Location:	Skarpnäcks Gård. 12 Skarpnäcks gårdsväg, Skarpnäcks Gård, 128 31. 10 minute walk from Skarpnäck. (59.2693, 18.1442)
Open:	no restrictions. [2021]
Fee:	free. [2021]
Classification:	Glacial Mill
Light:	n/a
Dimension:	Ø=1 m, VR=1.4 m.
Guided tours:	self guided
Photography:	allowed
Accessibility:	no
Bibliography:
Address:	Jättegrytan i Skarpnäck, 12 Skarpnäcks gårdsväg, Skarpnäcks Gård, 128 31.
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then. Please check rates and details directly with the companies in question if you need more recent info.

History

1925	kettle discovered during the construction of the road.

Description

Jättegrytan i Skarpnäck (Skarpnäck Giant's Kettle) is a small water-filled hole in the ground, with an iron railing. What looks so unimpressive, is actually the largest and best-preserved glacier mill in Stockholm. This is an impressive geotope though it is actually not underground, so we want to explain first, why it is listed on showcaves.com. The first reason is, that even vertical shafts are considered caves if they are big enough to be entered by man. The bigger ones are generally called daylight shaft or pothole. On the other side, this is a sort of very short gorge, and we also list gorges.

So it is obviously time to explain what this hole is. When the rock surface is covered by a glacier, the ice is often melting on the surface of the glacier, during summer for example. The melting water flows on the surface, reaches a shaft and enters a glacier cave. Typically, the water melts a shaft into the ice down to the bedrock, where it starts to flow on the surface downhill through a glacier cave. This kind of mill is formed at the point where the water reaches the bedrock after falling down the shaft. It has a lot of energy and starts to form a hole, later rocks are moved around the hole, and it works like a drilling machine. The result is a hole with rounded forms, which is actually the same as any dolly tub in a river bed or gorge. And if the shaft moves, for example by the moving glacier, series of such holes are drilled.

We said it is a water-filled hole in the ground, which is rather unfortunate. Fortunately this is a result of the rainy climate and after a dry periods, typically in summer, you may see it without water. Inside the hole is a huge rock, which was once swirled around by the water and helped to drill the hole.

Such kettles or glacier mills are not exactly rare. Nevertheless, the bigger ones are quite impressive and have been marked as a sight long ago, before the term geotope became known. They are found everywhere, where once a glacier existed. Stockholm has a handful of these kettles, one is even located in the basement of a courthouse, but this is the best-preserved and largest.