First backpacking trip for my 11 y/o son this past August. Three days/Two nights @ Porcupine Mountains Wilderness State Park in UP Michigan. He enjoys it more than my 15 y/o did when I took him on his first trip around the same age.
I also hiked the Pictured Rocks National Lakeshore and another trip into the "Porkies" with friends, but the dad/son trip was the best!