In fall 1805, the Lewis and Clark Expedition hurried toward the Pacific Ocean before winter, traveling faster than at any other time on the journey and often covering 30 miles or more per day on the swift water of the Snake River, though William Clark wished they could portage around more of the dangerous rapids because the season was so far advanced and time was precious. Clark wrote that Sacagawea's presence in this region signaled friendly intentions, since no woman accompanied a war party of Indians in that quarter. Following the advice of the Walla Walla people, the expedition took a good road with plenty of deer and antelopes that led travelers overland between the confluences of the Columbia and Walla Walla rivers and the Snake and Clearwater rivers, traveling about 100 miles on this route between April 30 and May 5, 1806. The expedition also encountered the semi-arid Columbia plain, now known as the Columbia Plateau, where Clark noted the absence of timber on the river, while Thomas Jefferson had instructed Meriwether Lewis to seek the most direct and practicable water communication across the continent for commerce. On Paráha Creek, a tributary of the Tucannon River, Lewis and Clark met a prominent Nez Perce chief known as the Bighorn Chief, whose son and grandson are believed by historians to have been the later leaders called Looking Glass, elder and younger.