For more than 20 years, the protected ‘Marinehaus,‘ originally a union club for naval officers, was left neglected in the central Berlin neighborhood, Mitte. Now the building, as a central part of the vision of the Berlin City Museum to establish a cultural cluster, is to be resurrected as a new museum typology. With a strong house-in-house concept, ADEPT wins the international competition ahead of 20 invited competitors.