The original railway line that takes tourists from Beijing to the Great Wall at Badaling has a rather impressive switchback to gain height just south of Badaling, as shown here on Openrailway map (copyright Openstreetmap)
There are separate switchbacks for going north and south (ish), each with a station (though not used as passenger stops any more).
Does anyone know of any similar configurations anywhere else (present or past)?
I think every one I've seen has been on single track - and also on a tourist line rather than one carrying a "proper" passenger service (albeit somewhat reduced now the high speed line, shown on the right hand of the map, is operating).

There are separate switchbacks for going north and south (ish), each with a station (though not used as passenger stops any more).
Does anyone know of any similar configurations anywhere else (present or past)?
I think every one I've seen has been on single track - and also on a tourist line rather than one carrying a "proper" passenger service (albeit somewhat reduced now the high speed line, shown on the right hand of the map, is operating).
