The Sea-maiden Sconce

The Sea-maiden Sconce (Skansen Hafsfrun in Swedish) is a sconce (a small protective fortification, such as an earthwork, often placed on a mound as a defensive work for artillery) which is not part of the original wall. It was built outside, but connected to, the wall in 1712 under the threat of Russian invasion. Eight cannons were placed at the sconce to defend the harbor and the south part of the wall. This was done at the same time as The Silver Cap (https://reveal.world/story/the-silver-cap), The North Gate (https://reveal.world/story/the-north-gate), and the East Gate (https://reveal.world/story/the-east-gate) were equipped with cannons and artillery. Neither the sconce nor the cannons were ever used in any actual war activity. 

Photo: W.carter