I saw a really good show about this on one of the history channels. The saboteurs were a mixture of elite soldiers (who knew nothing about nukes) and scientists (who had to learn how to shoot, ski, skydive and mountain climb in just a few weeks). The weapons plant was located on a cliff face with just one bridge crossing the gorge. The plan was to cross the bridge in the middle of the night, but they discovered that it was too heavily guarded. So, with no other option, they scaled down the 600-foot ravine, crossed the icy river, and then climbed back up the cliff to get to the plant. After the raid, they skied 250 miles to Sweden and escaped capture.