Stora Hästö by boat – a nature trail below and above the water

About 90 per cent of the Archipelago National Park is under water. On Stora Hästö, this world is easy to explore: the island's shallow waters are home to Metsähallitus's first underwater nature trail, whose information boards are attached to concrete slabs on the seabed and whose routes are connected by a rope.

There are two underwater routes. The Harbour Porpoise route (Pikkupyöriäinen), about 150 metres long, is marked with an orange rope and runs at a depth of about 1–1.5 metres, so you can follow it by snorkelling or swimming. Along the way you can see eelgrass, bladderwrack, blue mussels and harmless jellyfish, among other things. The Grey Seal route (Harmaahylje), about 300 metres long, is marked with a blue rope and is intended for scuba divers. Deeper down, at about five metres, there is also a rowing boat wreck sunk by Metsähallitus, which shows how a wreck becomes part of the seabed.

In the western part of the island, a nature trail of about 1.6 kilometres has information along the way about changes in the sea and water protection. The trail runs through forest and over rocks with plenty of ups and downs, and it offers fine sea views. Metsähallitus recommends walking it clockwise. Sheep graze on the island in summer.

The trip suits swimmers, snorkellers and families with children who want to see underwater nature, as well as anyone who enjoys a natural harbour with a picnic, a walk and a swim. The water is usually clear for almost the whole summer.

You can also rent the Buster Magnum from us for longer, as long as you need. Stora Hästö has a camping area, so the island offers a peaceful place to stay on a longer archipelago trip.

The natural harbour of Stora Hästö is a sheltered bay on the west side of the island. There is no jetty, so boats moor with the bow to the rock and the stern to an anchor. There are mooring rings on the south side of the bay, and the anchor holds well in the seabed. The depth is about 1.5–2.5 metres, and there are a few rocks along the shoreline, so look for a mooring spot with a suitable depth for the boat.

Drop the stern anchor well before the shore and slowly bring the bow to the rock. If mooring with a stern anchor is new to you, ask us for tips before you set off.

Important: anchoring near the underwater nature trail is not allowed, and the trail's buoys must not be touched.

The bay is sheltered from most winds, but a strong north-westerly or westerly wind makes the mooring spot uncomfortable. In that case, move to a more sheltered spot in good time, for example at the eastern end of the island.

On the shore there is an information point, a campfire site and a woodshed, as well as a dry toilet and a camping area. Always check whether a wildfire warning is in force before lighting a fire.

The starting point of the underwater nature trail is marked with a white buoy, and the texts on the information boards are in Finnish and Swedish. Exploring the deeper route and the wreck requires diving equipment, but in clear water you can see the bottom of the shallower route from the surface while snorkelling.

Stora Hästö is part of the Archipelago National Park, where everyman's rights do not apply as such. Read the national park's regulations before your trip. The service season runs from June to September.

There is no fuel on the island. Refuel on the way if needed, for example in Korpoström or Nauvo. The Buster Magnum runs on 98E5.