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When the Milwaukee Road (more formally known as the Chicago, Milwaukee, St. Paul, & Pacific Railroad) abandoned its tracks through Washington state in 1980, the state eventually acquired the right-of-way to be used as a basis for a recreational trail. Now called the Palouse to Cascades Trail, the trail construction has occurred in fits and starts, with gaps being filled in as funding allows.
One of the biggest gaps was here, where the Renslow Trestle now crosses Interstate 90 between Ellensburg and Vantage. The original timber trestle was built in 1908, then replaced by the present steel trestle in 1910. The steel trestle was built within the wooden trestle, a piece at a time, to minimize disruption of the rail traffic. The trestle crosses the canyon containing Johnson Creek (also called Park Creek), and is some 680 feet long, with a height of roughly 118 feet.
The route along the creek was much later followed, in the late 1960s, by Interstate 90. Conveniently, there was plenty of clearance for the freeway to be laid between the existing trestle supports and, of course, the trestle was amply high enough to clear the tallest vehicles.
The last passenger train crossed Renslow Trestle in May 1961, and freight trains stopped in March 1980. The rails all along the route were then salvaged. The rest of the right-of-way could then be converted to trail, but the trestle itself sat abandoned, a forlorn steel skeleton between the trail ends on either side. It was too dangerous to cross on foot, so hiking, biking, and horse traffic had to make a long detour between the ends of the trail.
As more of the trail was completed, agitation grew for the Renslow Trestle to be retrofitted to be safe for non-motorized traffic, and this finally occurred in the late 2010s. Prefabricated concrete slabs were laid on the trestle bed and guardrails were installed. The trestle opened in spring 2021.
Know Before You Go
The Renslow Trestle is freely open on the Palouse to Cascades Trail. It is most easily accessed from the Boylston (or Renslow) trailhead, which is near the trestle on the southeast side at about 46.95437 N, 120.29749 W. It is just off Stevens Road, which goes under I-90 but does not have access ramps to the freeway. To get to the trailhead, take Exit 115 off I-90, which is west of the trestle, onto Cleman Road. Go south about 1/4 mile and turn right on Badger Pocket Road (intersection about 46.95745 N, 120.41338 W). Follow Badger Pocket Road. It makes a right-angle turn to the south in about half a mile; keep going another 0.8 mile and turn left onto Carroll Road (at about 46.95651 N, 120.40158 W). Follow Carroll Road 1.5 miles and turn left onto Prater Road (at about 46.95651 N, 120.36936 W). Now take Prater Road 1.1 mile to the junction with Boylston Road (at about 46.96974 N, 12036248 W). Turn right here and follow Boylston Road 3.3 miles to a T-junction with Stevens Road. Boylston Road mostly parallels I-90 on the south, with views of Renslow Trestle as the road approaches it. At 3.1 miles the road crosses under Renslow Trestle.
From the T-junction, the trailhead parking area is to the right on Stevens Road a couple of hundred yards. A short connecting trail leads from the parking area up to the Palouse to Cascades Trail; turn right to get to Renslow Trestle
The Palouse to Cascades Trail is on the edge of the U.S. Army Yakima firing range through here; stay on the marked trail. Do not trespass onto the firing range!