To get there, take Exit 34 off I-90 and take a right. Follow 468th Ave until just before the steel truss bridge where a tiny brown sign reading Twin Falls directs you to take a left on 159th St. Follow this for about a half a mile to the trailhead. View Google Directions >>
The path begins gently, hugging the banks of the South Fork Snoqualmie River for just under a mile before starting a series of ups and downs. The rushing river is your friendly companion as you press toward the falls through a young forest of pine and alder. Find the path down to the lower falls near the two mile mark. It is a short 104 steps down to a the observation deck to take in the stunning cascade and look up at the 80 bridge spanning the river. Beyond the bridge, the trail winds up to an overlook of the upper falls before pushing onward to connect up with the John Wayne Pioneer Trail.
Accessible year round, this approachable trail is ideal for little hikers, as the falls make for a dramatic end to the hike. At the same time, because it is so easily accessible, it's a very popular trail, so you can expect some company on this little walk in the woods.
History
Much of this landscape has changed since old US10 was the primary thoroughfare for Snoqualmie Pass. The Twin Falls Recreation Area was the first of four parcels that now comprise Olallie State Park, acquired by the Parks Department in 1950 as plans were finalized for early phases of present day I-90. What was a short pullout and trail to the falls overlook on US10 became isolated with the advent of the new freeway. Despite the successful efforts to preserve the land as parkland, access to the falls nonetheless languished. Then, in the early 1980s, the Weeks Falls Hydroelectric Project just upriver from Twin Falls was brought online. This was followed swiftly by a project for Twin Falls, which ultimately led to the rebuilding of the trail in late 1989, as well as the helicopter-assisted bridge construction. However, all of the Twin Falls hydropower workings are underground or underwater, hidden from view.