The branch, which is probably seen as an insignificant twig by those who don't have experience of it, is probably the busiest "One engine in steam" branch in the country. Often run with a 3-car unit, which nevertheless at peak periods can have substantial standing. It's not just a tourist line, but a substantial commuter route, both for connections and for the local trip. Ever since the old Eton-Windsor bridge over the Thames was closed a generation ago it has formed a far more practical route between the two towns than the bus, which has to go round maybe three times the distance over the main road bridge, and due to traffic congestion can take considerably longer.