In April, the expedition left Fort Mandan and headed up the Missouri River in "pirogues". They had to be poled against the current and sometimes pulled from the riverbanks. On May 14, 1805, Sacagawea rescued items that had fallen out of a capsized boat, including the journals and records of Lewis and Clark. The corps commanders, who praised her quick action, named the Sacagawea River in her honor on May 20.