Line B () is a line on the Prague Metro. Chronologically the third to open, it was first opened in 1985 and continued to expand in the 1990s. Currently it is the longest line in the network with 24 stations and of track. History Rolling stock 81-71: 1985 - July 2009 81-71M: 2006 - present External links M. Peralta – Undergraduate research project. Includes a collection of statistical data for transect B (yellow line) on total entrances, and connecting bus & tram routes for each metro hub. Architecture photo series of all stations of B line (Prague Metro) Website is available in Czech, English and German Metro map Prague Metro Railway lines opened in 1985