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Washington State Route 504
State Route 504 (SR 504, designated as the Spirit Lake Memorial Highway) is a state highway in southwestern Washington state in the United States. It travels 52 miles (84 km) along the North Fork Toutle River to the Mount St. Helens area, serving as the main access to the Mount St. Helens National Volcanic Monument. The highway begins at an interchange with Interstate 5 (I-5) and SR 411 in Castle Rock and terminates at the Johnston Ridge Observatory near Spirit Lake.
The Cowlitz County government built the Spirit Lake Highway in 1903 and paved it in the early 1930s before it was transferred to state control, becoming Secondary State Highway 1R (SSH 1R) in 1937. SSH 1R initially ended at the boundary of Columbia National Forest (now Gifford Pinchot National Forest), but was extended in 1961 to the timberline of the mountain. It was renumbered to SR 504 in 1964 and remained popular with loggers and tourists, requiring bridges and sections to be rebuilt.
A major section of SR 504 was destroyed in the May 18, 1980, eruption of Mount St. Helens and its subsequent lahar on the North Fork Toutle River. The state government rebuilt most of the highway from 1988 to 1997, relocating it further north and connecting to new interpretive centers at Coldwater Ridge and Johnston Ridge. A part of the old alignment near the Toutle River Sediment Dam is signed as a spur route. Continued volcanic activity at Mount St. Helens, particularly in the mid-2000s, has resulted in closures and evacuations along the highway at various times.
SR 504 begins as an extension of Huntington Avenue at an interchange with I-5 northeast of Castle Rock. The street continues southwest into downtown Castle Rock as SR 411 and I-5 Business. SR 504 travels northeasterly through a small commercial area before ascending into the hills above Salmon Creek, passing several farms and wineries along the way. The highway follows a minor stream heading southeast into the wetlands around Silver Lake, where the Mount St. Helens visitor center and Seaquest State Park lie. SR 504 continues along the north side of the lake and passes through the town of Toutle at the confluence of the Toutle River's two forks.
The highway crosses over the river on the Coal Bank Bridge and continues along the north side of the North Fork Toutle River, following the narrow valley to the east of Beigle Mountain. Near the Riverdale Raceway, SR 504 intersects the east end of SR 505, which provides connections to I-5 and Toledo. The highway continues northeast into Kid Valley, home to camping sites and a few homes, and follows the south side of the narrower valley as the river meanders north and south around various mountains. At a third crossing of the river, SR 504 intersects a short spur route on Sediment Dam Road that leads to a viewpoint overlooking the Toutle River Sediment Dam. The highway continues along the northeast side of the earthen dam and its reservoir, climbing uphill and running through cuts in the cliffs.
Further southeast along the river, SR 504 passes the privately owned Eco Park resort, a youth camp, and a heliport near the Hoffstadt Bluffs Viewpoint. The highway then crosses over Hoffstadt Creek on a 2,340-foot (710 m) steel truss bridge that sits 370 feet (110 m) above the valley floor; it is the longest of 13 bridges on SR 504. The bridge also marks the western extent of the "blast zone," where trees were felled during the 1980 eruption of Mount St. Helens, located 12 miles (19 km) away. The area has large forests of young fir, pine, and cottonwood trees planted by Weyerhaeuser in the 1980s as part of a regeneration and restoration project. The company also operates the Charles W. Bingham Forest Learning Center, a museum that overlooks the North Fork Toutle River and also includes a rest area.
SR 504 continues further into the mountains, crossing Bear Creek and traveling around Elk Rock to a viewpoint on its southeast side. From the Elk Rock area, the highway forms the northern boundary of the Mount St. Helens National Volcanic Monument and encounters more mountainous terrain that results in several hairpin turns between other scenic viewpoints. After crossing several branches of Maratta Creek, SR 504 reaches a partial cloverleaf interchange with an access road that serves the Coldwater Science and Learning Center, a visitor center that overlooks the mountain and open from autumn to spring. The highway heads west before completing a hairpin turn to travel south around the end of Coldwater Lake. Beyond milepost 45, SR 504 is closed during the winter months due to hazardous conditions for drivers and potential avalanches. It typically reopens in time for the May 18 anniversary of the 1980 eruption.
The highway continues into the National Volcanic Monument and turns east before reaching the border between Cowlitz and Skamania counties. SR 504 follows South Coldwater Creek upstream through a narrow valley to its headwaters near Spirit Lake, passing several trailheads, and turns west to continue its ascent. The treeless landscape is home to winter herds of Rocky Mountain elk and deer. The highway turns east once again near the Loowit Viewpoint and reaches the Johnston Ridge Observatory, the volcano's main visitor center open from spring to autumn and situated at an elevation of 4,314 feet (1,315 m). SR 504 terminates downhill from the observatory at its parking lot, located 5.5 miles (8.9 km) north of the Mount St. Helens crater.
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Washington State Route 504
State Route 504 (SR 504, designated as the Spirit Lake Memorial Highway) is a state highway in southwestern Washington state in the United States. It travels 52 miles (84 km) along the North Fork Toutle River to the Mount St. Helens area, serving as the main access to the Mount St. Helens National Volcanic Monument. The highway begins at an interchange with Interstate 5 (I-5) and SR 411 in Castle Rock and terminates at the Johnston Ridge Observatory near Spirit Lake.
The Cowlitz County government built the Spirit Lake Highway in 1903 and paved it in the early 1930s before it was transferred to state control, becoming Secondary State Highway 1R (SSH 1R) in 1937. SSH 1R initially ended at the boundary of Columbia National Forest (now Gifford Pinchot National Forest), but was extended in 1961 to the timberline of the mountain. It was renumbered to SR 504 in 1964 and remained popular with loggers and tourists, requiring bridges and sections to be rebuilt.
A major section of SR 504 was destroyed in the May 18, 1980, eruption of Mount St. Helens and its subsequent lahar on the North Fork Toutle River. The state government rebuilt most of the highway from 1988 to 1997, relocating it further north and connecting to new interpretive centers at Coldwater Ridge and Johnston Ridge. A part of the old alignment near the Toutle River Sediment Dam is signed as a spur route. Continued volcanic activity at Mount St. Helens, particularly in the mid-2000s, has resulted in closures and evacuations along the highway at various times.
SR 504 begins as an extension of Huntington Avenue at an interchange with I-5 northeast of Castle Rock. The street continues southwest into downtown Castle Rock as SR 411 and I-5 Business. SR 504 travels northeasterly through a small commercial area before ascending into the hills above Salmon Creek, passing several farms and wineries along the way. The highway follows a minor stream heading southeast into the wetlands around Silver Lake, where the Mount St. Helens visitor center and Seaquest State Park lie. SR 504 continues along the north side of the lake and passes through the town of Toutle at the confluence of the Toutle River's two forks.
The highway crosses over the river on the Coal Bank Bridge and continues along the north side of the North Fork Toutle River, following the narrow valley to the east of Beigle Mountain. Near the Riverdale Raceway, SR 504 intersects the east end of SR 505, which provides connections to I-5 and Toledo. The highway continues northeast into Kid Valley, home to camping sites and a few homes, and follows the south side of the narrower valley as the river meanders north and south around various mountains. At a third crossing of the river, SR 504 intersects a short spur route on Sediment Dam Road that leads to a viewpoint overlooking the Toutle River Sediment Dam. The highway continues along the northeast side of the earthen dam and its reservoir, climbing uphill and running through cuts in the cliffs.
Further southeast along the river, SR 504 passes the privately owned Eco Park resort, a youth camp, and a heliport near the Hoffstadt Bluffs Viewpoint. The highway then crosses over Hoffstadt Creek on a 2,340-foot (710 m) steel truss bridge that sits 370 feet (110 m) above the valley floor; it is the longest of 13 bridges on SR 504. The bridge also marks the western extent of the "blast zone," where trees were felled during the 1980 eruption of Mount St. Helens, located 12 miles (19 km) away. The area has large forests of young fir, pine, and cottonwood trees planted by Weyerhaeuser in the 1980s as part of a regeneration and restoration project. The company also operates the Charles W. Bingham Forest Learning Center, a museum that overlooks the North Fork Toutle River and also includes a rest area.
SR 504 continues further into the mountains, crossing Bear Creek and traveling around Elk Rock to a viewpoint on its southeast side. From the Elk Rock area, the highway forms the northern boundary of the Mount St. Helens National Volcanic Monument and encounters more mountainous terrain that results in several hairpin turns between other scenic viewpoints. After crossing several branches of Maratta Creek, SR 504 reaches a partial cloverleaf interchange with an access road that serves the Coldwater Science and Learning Center, a visitor center that overlooks the mountain and open from autumn to spring. The highway heads west before completing a hairpin turn to travel south around the end of Coldwater Lake. Beyond milepost 45, SR 504 is closed during the winter months due to hazardous conditions for drivers and potential avalanches. It typically reopens in time for the May 18 anniversary of the 1980 eruption.
The highway continues into the National Volcanic Monument and turns east before reaching the border between Cowlitz and Skamania counties. SR 504 follows South Coldwater Creek upstream through a narrow valley to its headwaters near Spirit Lake, passing several trailheads, and turns west to continue its ascent. The treeless landscape is home to winter herds of Rocky Mountain elk and deer. The highway turns east once again near the Loowit Viewpoint and reaches the Johnston Ridge Observatory, the volcano's main visitor center open from spring to autumn and situated at an elevation of 4,314 feet (1,315 m). SR 504 terminates downhill from the observatory at its parking lot, located 5.5 miles (8.9 km) north of the Mount St. Helens crater.