Granvikin Hylky

Granvikin Hylky is a small, partially collapsed wooden vessel of about ten metres on the northern flank of Djupdalen sound, southern side of Stortervolandet island in the inner Pargas archipelago. The bottom is at fifteen metres, the shallowest standing timbers around twelve. Both keel ends survive, with a relatively sharp bow profile, a double-ended hull, and at least one mast position; the wreck lies on a heading of one-six-five degrees. Bottom type is not specified in either canonical source, though a strait-floor site in the inner archipelago is typically muddy or muddy-sand. There is no buoy, no descent line, and no surface infrastructure; reaching the wreck means a small private boat from a Pargas or Nagu launch and a GPS mark on the Heritage Agency coordinates.

The vessel's identity is not resolved. The Heritage Agency dates the wreck only as historical, undefined; there is no recorded ship name, no build year, and no sinking event. What is documented is the discovery: the local Pargas dive club Pargas Tumlare rf located the wreck in 2008 after rumours of its existence prompted a sonar search, and the Barlius dive group returned in 2022 to sidescan-survey the site and produce the imagery and corrected coordinates that the catalogue carries today. The hylyt.net title carries a trailing "1", which raises the possibility of sister wrecks at the same site labelled 2, 3 and so on, but no such siblings have surfaced in the catalogue.

Practical access is a private boat from a Pargas or Nagu small-boat harbour, not from Hanko. Pargas Tumlare rf is the obvious local point of contact, but no commercial centre runs a programmed dive to this wreck. Brackish Baltic conditions apply: drysuit standard from May through October, surface temperatures 15-22 °C in summer, bottom typically 4-8 °C below the thermocline. Compass and SMB are baseline kit on any unmarked archipelago dive from a free-floating boat. The Antiquities Act is categorical: no touching, no anchoring on the wreck, no recovery of any item from the seabed.