This private island is located in Trégastel, France. Dubbed “Château de Costaérès”, the historic home was built in 1895 by the Lithuanian-Polish mathematician, engineer and inventor Bruno Abdank-Abakanowicz. It features over 3,000 square feet of living space with 5 bedrooms, 3 full and 4 half bathrooms, living & dining rooms, kitchen, gym, sauna and more.
Outdoor features include outbuildings, swimming pool, two sandy beaches and two landing stages for travel between the mainland and the island.