Probably Grand Canyon to Brackett Field, routing via Meteor Crater and Sedona (not landing at either due crosswind). 3 hours 45 minutes total time, distance something like 450nm.
Fabulous trip - done something very similar since as "pax" in RHS. That's the upper limit of bladder tolerance for an oldie like me.
Done some other very enjoyable trips, similar distances, but broken into smaller chunks with food and comfort breaks on the way. Wouldn't want to do the Greenland to USA one!