The Sol Duc River starts high in the Olympic Mountains and takes a long, lazy path west before joining the Bogachiel River and flowing to the sea near La Push. The Sol Duc access road follows the river and has a number of pull outs for viewing the river. There's even a pull out at the Salmon Cascades where, in season, one can watch those magnificent fish leaping upstream. The road ends shortly after the Sol Duc Hot Springs Resort, noted for its geothermal springs. You can soak in these springs, but the naturally heated mineral waters are channeled into what appears to be a conventional swimming pool.
The area is full of trails, but the main trailhead is past the resort, past the campground, at the true end of the road. Here a trail takes you thirty minutes into the forest to the spectacular Sol Duc Falls themself. There are other lesser falls on the way, but the main show is ahead. The trail descends a bit. Set in a valley of green are the wild waters roaring loudly, pouring over the rocks, blasting their way under the bridge then jetting out into the river beyond.
Sol Duc Falls is actually just the start. It is an entry point into the high country including the High Divide. You can climb another 1600' following Canyon Creek to Deer Lake and then another 800' to the wilderness of the glacial potholes. You can continue to the High Divide itself. Alternately, you can follow the Sol Duc River into the mountains or take a loop on the far side of the river back to the resort.
NOTES: The walk to the falls is short, but other options abound. Get a map and ask about trail conditions at the resort. The hot springs are accessible from a swimming pool. If you want to stay at the resort during the summer, book early.
Time: 1:10, to the Potholes 4:00
Driving time from Port Angeles: 1:30
Admission: ONP admission required
Facilities: Bathrooms, Sol Duc Hot Springs Resort with lodging and dining, pay phone