My first, and biggest solo trip was on the Sheenjek river in Alaska. I flew to Anchorage, Fairbanks and Fort Yukon where I hopped on a bush plane. The pilot took me up to the highest navigable water near the continental divide in the Brooks range where we dropped most of my kit (surrounded by a solar electric fence to keep the bears off). Then he flew me another 15 miles upstream and left me. I hiked for a few days back to my stuff and then floated for 25 days down the Sheenjek to the Porcupine and I took the Porcupine to the Yukon at Fort Yukon. I used my 16' Ally pack boat. Beautiful river. Not too crowded. I brought a VHF radio so that if I got into trouble I would be able to call a passing plane for help. Now when I go on solo trips I bring a SPOT tracker which has an SOS button that should send in the cavalry if things start hitting the fan.