Tuesday, February 19, 2013

Hike site of earthquake from 500 million ya

Upper Falls. Photo courtesy of Wisconsin DNR.
Hikers can view the results of an earthquake from 500 million years ago while walking the island trails at Amnicon Falls State Park near Superior, Wis.

Known as the Douglas Fault, this split in the earth stretches from Ashland, Wis., to near the Twin Cities. Much of the bedrock sits at 50-60 degree angles, offering sights reminiscent of the modern San Andreas Fault. All of these millennia later, the fault line still effects the course of rivers – which is to hikers’ visual delight.

To reach the state park, take U.S. Hwy. 2 east from Superior. Turn left, or north, onto County Road U. The park entry is in a third of a mile. A vehicle admission sticker is required to enter.

Continue past the contact station across the bridge over the river and park in the first lot to the right; if it’s full, continue on, taking the first road to right for another lot. Presuming you got a parking space in the first lot, pick up the trail at the picnic shelter and go right toward the Amnicon River. Listen for the sound of gurgling water, present the moment you open your vehicle’s doors.

Because of the river’s high mineral content, the waterway sometimes can appear the color of root beer; it’s clean, though, and swimming is allowed in designated areas. The river ultimately meanders north, flowing into Lake Superior.

River island
The trail follows the Amnicon for about a quarter mile past another parking area and shelter (if you parked in the second lot, this is where you pick up the trail). Cross the river over a footbridge, which deposits you on an island where the waterway splits into two channels.

Go left for a view of Snake Pit Falls. While not particularly wide, the falls is 25 feet high with the water channeled between two stone works.

Continuing on, the trail loops around the island, offering a view of where the river divides. You also can garner a view of Lower Amnicon Falls. It tumbles over sandstone laid here more than 400 million years ago when streams flowed into a warm tropical ocean that covered Wisconsin.

The trail from there crosses the river via the 55-foot long Horton covered bridge, one of the park’s major attractions. Originally a highway bridge at another spot on the Amnicon, it was moved here in 1930. It is one of only five Horton bridges that still exist. Besides experiencing history, hikers crossing the bridge are afforded two picturesque views as well – you can see waterfalls from both sides.

Lower and Upper Amnicon falls
After crossing the bridge off the island, go left for a different view of Lower Amnicon Falls. Erosion has smoothed out the sandstone cliff here.

You might be pleasantly surprised by the amount of wildlife at the park. Black bear, coyote, fox, porcupine, raccoon, squirrels and whitetail deer abound. Beaver, mink and otter – or at least their tracks – often can be spotted along the shore. A number of birds, including ruffed grouse and songbirds, also can be seen.

Backtrack and at the bridge continue straight, walking along the river banks for a view of Upper Amnicon Falls. The river rumbles over dark basalt, or solidified lava that formed here a billion years ago.

Canadian boulders and glacial potholes
If you’ve noticed a number of gray, sparkling boulders, that’s nonnative rock. The stone is just tens of millions of years old; glaciers brought this granite gneiss from Canada during the last ice age. Potholes in the rock also are fairly recent; swift-moving waters from melting glaciers drilled them out only a few thousand years ago.

Return to the bridge and cross back to the island. Go left for an island view of Upper Amnicon Falls.

Finally, cross the first bridge you took to reach the island. Follow along the same the path that you originally took to the island, maybe pausing for a picnic or snack. Past the second water source, the trail splits; go right to get back to your vehicle.

Read more about Douglas County day hiking trails in my Day Hiking Trails of Douglas County guidebook.