Opalsøen

Opalsøen is a lake in which you can swim, surrounded by steep cliffs. The lake is a remnant of the time when granite was quarried here. You can jump into the water from the 7-metre-high cliff edge, if the temperature and mood permits, or you can experience the lake by walking through the undulating natural surroundings.

Opalsøen is located next to Bornholm’s northernmost hillock, Hammerknuden, a unique natural area characterised by sea, cliffs and rocky heathland. Close by is Bornholm’s largest lake, Hammersøen, which forms the bottom of the rift valley that partially divides Hammerknuden from the rest of Bornholm.

In the past, granite quarrying was an important industry on the island, and the quarry at Opalsøen, Hammerbruddet, was active from the 1880s until 1971. The quarry was afterward included when Hammerknuden became a preserved area. The deepest part of the quarry has since filled up with water, and today this water constitutes Opalsøen. Apart from Opalsøen, you can find remains of other old stone quarries scattered over North Bornholm.

If you have a head for heights, in the summer you can glide down over the lake on an aerial ropeway from one of the clifftops. You end your trip down by landing in the water. If you want further adventures, you can also climb and abseil on the cliffs. There are a number of parking spots near the lake.