Up in the northeast corner of California is Tule Lake National Monument. The site is small, but remembers the largest concentration camp in the United States. During WWII, the area that is now Tule Lake National Monument was first a CCC camp, then a Japanese concentration camp, and eventually a POW camp. The site consists of several different locations that visitors can stop off at. It is not very developed currently and has a small visitor center for visitors to learn more. Additionally, there are tours offered, but visitors must make them in advance. When we visited, we stopped at a couple of sites and walked through the visitor center. Although the site is not large, we definitely recommend a visit to learn more.