Tsar Peter I officially founded the first Russian naval base, Taganrog (Turkish form: "Taygan" in Ottoman sources) on September 12, 1698. Taganrog became one of the first Russian cities built according to a detailed plan. Vice-Admiral Cornelis Cruys, who is regarded as the architect of the Russian navy, became the first mayor of Taganrog city in 1698–1702; in 1711 he produced the first maps of the Sea of Azov and of the Don River. The project for planning and building works in the city was established in 1698, based on the instructions provided by the tsar.