The project is located in the historical center of İstanbul which had been the capital city of three big empires. It is a renewal and structural empowerment project in this culturally rich area -The Historical Peninsula- which has a heritage value for all over the world. The existing building has been used as a guest house and office by Eti Maden İşletmeleri since 1974. It will be renewed to correspond today's requirements as a guest house with a contemporary facade design approach. The project has a critical attitude towards the neoclassic, kitsch facade renewals that threatens the The Historical Peninsula and has no connections with the İstanbul. The white crystalline image of the bor minerals produced by Eti Maden İşletmeleri is used in the facade. The facade made of white opaque U glass modules of 33 cm recalls the iamge of these bor minerals. In the interior, these glass walls make a semi-transparent affect. The elegant and plain facade, makes a modest statement in the texture of The Historical Peninsula.