Along the Ströömi shipping channel, which bisects the archipelago of the municipality of Kustavi, rises Villa Sarvilinna, whose tower is visible to mariners from far away. The villa and its surrounding grounds form a noteworthy cultural and architectural site, as well as a peculiar landmark of the island of Lypertö.
The villa was commissioned by Dr Oskar Alarik Hornborg (1870–1936), the City Physician of Pori, and his wife Varma (1882–1974). It was designed by the architect Lars Sonck; construction was completed in 1922. Constructed of round logs, this magnificent building and its original furniture have been listed in accordance with the Act on the Protection of Buildings, the only such site in the Archipelago Sea area.