KGS, acronym for Kartlı Geçiş Sistemi (literally: Pass System with Card), was an electronic toll collection system of contactless smart card type available on toll roads and toll bridges in Turkey. It was abolished on 1 February 2013.[1] The system was adopted to avoid traffic congestion at toll plazas. An alternative to KGS is the OGS system of radio-frequency identification (RFID) transponder type implemented on at the same toll plazas initially.
The KGS was launched in January 2005, and was first installed on the toll bridges Bosphorus Bridge on O-1 and Fatih Sultan Mehmet Bridge on O-2 over the Istanbul Strait. The smart card system was later extended to the intercity motorways O-3, O-4, O-32, O-51 and O-52. The KGS was in use on all toll roads in the country alongside the OGS until it was replaced by HGS.[2][3][4]
Developed by ASELSAN, the system is administrated by the General Directorate of Highways (Turkish: TC Karayolları Genel Müdürlüğü, KGM).[4][5]