Washington State Route 906

State Route 906
SR 906 is highlighted in red.
Route information
Auxiliary route of I‑90
Defined by RCW 47.17.850
Maintained by WSDOT
Length:	2.65 mi (4.26 km)
Existed:	May 11, 1967 – present
Major junctions
West end:	I‑90 in Snoqualmie Pass
East end:	I‑90 in Hyak
Location
Counties:	King, Kittitas
Highway system
State highways in Washington Interstate US State Scenic Former PSH 1964 renumbering Former ← SR 904 SR 908 →

State Route 906 Spur
Location:	Hyak, Washington
Length:	0.43 mi (0.69 km)

State Route 906 (SR 906) is a 2.65-mile-long (4.26 km) state highway in the U.S. state of Washington, serving Snoqualmie Pass and its associated ski areas in King and Kittitas counties. The highway travels southeast between two interchanges with Interstate 90 (I-90) in Snoqualmie Pass and Hyak. SR 906 was formed out of segments of the former Sunset Highway that were bypassed by the construction of the controlled-access Interstate Highway over the pass. Between 360 and 2,100 vehicles use the road on an average day in 2012.

SR 906 begins at a half-diamond interchange with I-90, exit 52, in Snoqualmie Pass, King County. North of I-90, Summit Road provides access to the Alpental ski area. Only the first ³⁄₁₀ mile (480 m) of the highway is in King County, with the remainder of the highway in Kittitas County. After crossing the county line, SR 906 is bounded by Summit West on the west side of the highway and the Snoqualmie Pass Traveler's Rest rest area on the east side. Access to the Pacific Crest Trail is provided from the one of Summit West's parking lots. Just south of the rest area is an intersection with Yellowstone Road, which links back to I-90 at a full diamond interchange. Yellowstone Road was once a part of the Yellowstone Trail, a cross-country auto-trail.