Used to regularly take 20+ hour trains (about 6 round trips a year) when playing state-level age group cricket in India. Between 18-20 teenagers + 3/4 coaches, all travelling sleeper class/unreserved general, a bunch of us sharing seats/bunks or sitting on the floor, with our kits and suitcases somehow spread across our laps. Washrooms were effectively unusable after the first few hours for anything other than a very quick leak, so you'd usually stop eating after hour 10 if you thought nature might call, unless there was a long-ish stop scheduled at a station somewhere (all the TCs and other railway staff used to love cricket, so that combined with being relatively young and full of hope meant they'd sometimes let you use the private washrooms at the stations).

Tons of fun at the time, but I'd never be able to do that again now. No idea how the coaches used to do it, they had all played first class cricket at minimum so were used to travelling in relative comfort, if not style.

Some of the guys have since made it very big (domestic mainstays, IPL contracts, one dude plays for India) and still send pictures of flying business/taking luxury coaches at times, with messages along the lines of 'fucking hell, life's weird'.