A unique island estate in the Tammisaari archipelago, formerly serving as the prestigious reception premises of the legendary Kansallis-Osake-Pankki (KOP), now elegantly renovated for private use.

Located just outside Tammisaari on the island of Orrholmen, the estate was originally designed by architect Heikki Siren as KOP’s exclusive representative venue. In 2006, the property was thoughtfully transformed into a private residence, blending timeless design with modern comfort. The charm of this island complex lies in its truly unique character. Private island properties of this scale, with optimal location and enduring architectural design, are exceedingly rare in Finland today.

All buildings on the island, the main residence, guest house, and sauna, are positioned with such harmony in the natural terrain that their placement can only be fully appreciated in person. The morning sun rises over the sea, gently waking those staying in the guest house and the master bedroom of the main building to a new day in the archipelago. Large south-facing terraces provide sheltered outdoor living spaces for enjoying the sun throughout the day, regardless of prevailing wind directions. In the evening, the sun shines into the spacious dining area adjoining the living room, onto the so-called “crayfish porch,” the sauna's generous terrace, and the swimming beach.

As winds continue to intensify across the Finnish archipelago, it is increasingly valuable to have a property where one can enjoy summer's finest moments sheltered from every direction, something this estate offers in full. Multiple swimming spots are available throughout the day, including a small sandy beach ideal for children. Boats can be moored in various sheltered docks and coves around the island, depending on wind direction. Wide, illuminated pathways connect the buildings, ensuring easy and safe movement. At dusk, the island’s ancient pine trees, survivors of archipelago conditions, create a magical ambiance — and can also be lit for added atmosphere.

The island comfortably accommodates up to 16 people across eight bedrooms, most of which feature en-suite bathrooms. Siren’s architectural signature remains clearly visible, while the renovation has brought the interiors in line with contemporary needs through timeless, stylish design and high-quality materials.

The drive from Helsinki to the Sommaröstrand marina takes just under two hours, followed by a sheltered 10-minute boat ride by water taxi, accessible in all weather conditions. For a faster arrival, the island is also accessible by helicopter.

If Orrholmen feels like your new private island paradise, please don’t hesitate to get in touch for further information or to arrange a private viewing.