The first Metropolitan Railway steam locomotives were ordered in 1864 for the Metropolitan Railway, to replace the Great Western Railway locomotive that had opened their first line the previous year. A total of 116 locomotives were built, of which two survive in preservation.
“The railway was hailed a success, carrying 38,000 passengers on the opening day, using GNR [Great Northern RailwayOffsite Link] trains to supplement the service. In the first twelve months 9.5 million passengers were carried and in the second twelve months this increased to 12 million. The original timetable allowed 18 minutes for the five intermediate stations.
Source: http://www.historyofinformation.com/expanded.php?id=3867, https://en.wikipedia.org/wiki/Metropolitan_Railway_steam_locomotives