Kustaanmiekka is home to Suomenlinna’s original bastion and a late-19th-century Russian defence line, complete with sand embankments and artillery points. It also offers spectacular views to the sea.

The sand-topped embankments at Kustaanmiekka formed part of the Russian defence front. A number of decommissioned guns and the powder magazines that served them can still be found on the embankments. The marked path goes around the Kustaanmiekka island.

The grass-covered embankments on the island were gradually built by the Russian military from the 1850s to the 1880s to form part of a new naval defence. The embankments were built in a geometric design using sand and peat. Connecting corridors and crew shelters were built between the gun emplacements. The soil brought from outside Viapori for the earthworks also contained the seeds of various invasive plants. These continue to thrive in Suomenlinna to this day.

The embankments are susceptible to erosion and are home to sensitive vegetation. For this reason, we ask that you stay on the marked routes.