Lower Klamath, located in both Oregon and California, was established by Teddy Roosevelt in 1908 to preserve a two-million-year-old nesting and feeding ground for migratory birds that was nearly destroyed in the early 1900s by irrigation and hunting. At 53,600 acres, this marshy refuge is the largest of six in the Klamath Basin and provides resting and brood-rearing habitat for tens of thousands of snow geese and other waterfowl. Nine years after it was made a refuge, the lake turned into a dry alkaline dust bowl when railroad construction blocked its main water source. A tunnel dug in 1942 from Tule Lake to Lower Klamath revived the lake. A 15mi driving-tour route traverses the dikes and marshlands and offers bird-watching opportunities.