Without a doubt, this one of my all-time favourite documentaries.
Dick Proenneke retired at age 50 in 1967 and decided to build his own cabin on the shore of Twin Lakes in Alaska. The first summer he scouted for the best cabin site, and cut and peeled the logs he would need for his cabin. He returned the next summer to finish the cabin where he lived for over 30 years.
You can buy the videos here.