Neglinnaya River
The first plans to rebuild the Neglinnaya River, presented in 1775, materialized in 1792. A new masonry canal, one sazhen (2.13 m) wide, was laid parallel to the Neglinnaya; after diverting water into the channel, builders filled the old river bed with earth. After the Fire of Moscow (1812), the canal was so polluted that the city cleared it and covered with a masonry vault, creating the first Neglinnaya Tunnel (1817-1819), which also formed present-day Neglinnaya Street and Theatre Square. Before centralised city sewage (1887), the tunnel doubled as a sewer, dumping the refuse into the Moskva River.