High Quality Content by WIKIPEDIA articles! OLT (Norwegian for Offentlig Landmobil Telefoni, Public Land Mobile Telephony), was the first land mobile telephone network in Norway. It was established December 1, 1966, and continued until it was obsoleted by NMT in 1990. In 1981, there were 30,000 mobile subscribers, which at the time made this network the largest in the world.