> 5 ft 6 in / 1,676 mm, a broad gauge, is the track gauge used in India, Pakistan, western Bangladesh, Sri Lanka, Argentina, Chile, and on BART (Bay Area Rapid

> 5 ft 6 in / 1,676 mm, a broad gauge, is the track gauge used in India, Pakistan, western Bangladesh, Sri Lanka, Argentina, Chile, and on BART (Bay Area Rapid Transit) in the San Francisco Bay Area. https://en.wikipedia.org/wiki/5_ft_6_in_gauge_railway https://en.wikipedia.org/wiki/5_ft_6_in_gauge_railway So actually it _is_ common - mostly in and around India. So maybe here is the original vision for the BART: https://youtu.be/fWk36h9-meE https://youtu.be/fWk36h9-meE ;-)