After sponsoring the Wilderness Act of 1964 and the Wild and Scenic Rivers Act in 1968, Senator Frank Church continued to pursue legislation to protect over one million acres in central Idaho, formerly known as The Idaho Primitive Area. Cecil D. Andrus built on the conservation foundation laid by Frank Church, and as Interior Secretary he accompanied President Carter and his family on a three-day rafting trip down the Middle Fork of the Salmon River in 1978. Later that year, a proposal to designate the central Idaho wilderness was sent to Congress, and in 1980 legislation passed creating the Frank Church River of No Return Wilderness. The legislation also added 125 miles of the Salmon River to the Wild and Scenic Rivers System. At more than 2.3 million acres, the Frank Church Wilderness is the second largest wilderness area in the lower 48 states.