Road trip from uk to spain through France, visiting family and lots of places along the way. We drove back through a different route to see other parts of France then back to UK.
Road trip around the south ialand of NZ, we did a loop, from the top of south island through the east coast down to Stewart Island, then back through the west coast.
Driving from Chrustchurch to Auckland in 2 days once in NZ.
One road trip from France, through Belgium, Luxemburg, Germany, Switzerland, Italy, south of France then back to the north of France.
38 hrs trip by overnight train in China from Nanjing to Guilin, that was more than 20 yrs ago before high speed trains.
Im not sure which one is the longgest though.