Schwalbe marathons handle a mix of road and rail trail well,
move fairly well on the road and provide some traction on the sand/gravel/limestone
trail surface; especially if there is a mucky section or places after a rain.
plus the marathons are fairly puncture resistant and last well,
my wife, teenage son and myself did the erie canal trail last summer,
682 km- no flats or tire problems among us. another pair of riders had
marathons, they didn't have any tire problems either, lots of other cyclists
had frequent flats.