This page was designed to collate country and city data collection examples, and data availabilities, of statistics concerning metros (subways/undergrounds) and trams in different UNECE countries. The focus of the statistical output will be passenger numbers and passenger-km. The goal was to consider whether it is feasible to collect these at the international level, while hopefully guarding the city-by-city breakdown. Given the good data availability, UNECE proceeded with a pilot collection and published the results in May 2020. See the data and further details here: https://www.unece.org/trans/main/wp6/map_tram_metro_dataset.html.