
Hopefully I can arrange this information in an orderly fasion. Please bear with me here. Here I list each land vehicle, followed by the current lowest level of road improvement it can travel on, followed by the proposed lowest level of road improvement accesible.
Vehicle - current - proposed
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bike - path - path
bike cart - path - path
rickshaw - path - path
tandem bike - path - path
tricycle - path - path
small wooden cart - path - path
dirt motorcycle - path - path
road motorcycle - paved road - paved road
jeep - path - path
pickup - path - sand road
small pickup - path - path
small tractor - sand road - sand road
tractor - sand road - paved road (if we consider it as a tractor trailer NOT a farm tractor)
mini van - sand road - sand road
small van - sand road - sand road
van - sand road - paved road
caddie - sand road - paved road
limousine - sand road - paved road
passenger car - sand road - sand road
small sportscar - sand road - paved road
stationcar - sand road - sand road
bus - sand road - paved road