 After the approval of the metro line by the city's Monument Protection Board and the completion of the tunnels relating to the metro line, a construction bid for the metro bridge spanning the Golden Horn was published by the Metropolitan Municipality.By 2005, a total of 21 proposals were submitted to the Monument Protection Board; however, none were found to be sufficiently in harmony with the city's skyline.A successful design, by architect Hakan Kıran, was controversial from the very beginning.