Captain George B. McClellan and his lieutenant Abiel W. Tinkham explored the Snoqualmie Pass region in 1853 and 1854. Their goal was to find a pass better suited for a railroad than Naches Pass, where the Naches Trail crossed the Cascade Mountains. They explored from the east side of the mountains, reaching the vicinity of Yakima Pass (). Tinkham continued down the west side via the Cedar River. McClellan decided not to examine Snoqualmie Pass itself because of unfavorable reports from Natives.