Rails for horsecars (called "konka" (конка) in Russian) were installed in Moscow since 1872, however, the first lines were built on radial streets; rail construction on Garden Ring peaked in 1891. Likewise, the first electrical tram was launched in 1899, but Garden Ring was electrified in 1907-1910. Circular line traversing the Ring was known as the ""B" route" (or a "bug" (букашка) in popular language). Gradually, new rental housing of 4, 5, and 6-story buildings replaced the old two-story blocks; Moscow's tallest "skyscraper", an 8-story Art Nouveau Afremov Building, was inaugurated in Sadovaya-Spasskaya Street in 1904.