We stayed at the North Cascades Institute for the weekend, so we had quick access to this hike. You're not going to drive 3 hrs to do it, but it is worth a stop combined with another short hike. You also get to drive across the Diablo Dam with the scenic lights along the road. TH is by the parking lot for the PUD and NCI, the trail goes to both Sourdough Falls and hits the trail for Diablo Lake, everything is well signed. It is a mellow lollipop loop with mild switchbacks and good tread. When you get close to the Sourdough Falls there are some rock stairs up along the creek. The Falls are to your right; I had to stand in a shallow stream to get my picture. Nice fall color right now and LOTS of different kinds of mushrooms! There are loos by the PUD parking lot. 

I got to Diablo Dam at about 7am and was confronted with a Road Closed sign backed up by a phalanx of highway megamachinery. I parked up on the side of State Route 20 and walked to the trailhead, adding an extra 1.2 miles to each end of my hike. Don’t do what I did. The road is closed for work at night, but it should open at 5am and you can drive across the dam. The sign was still set at Road Closed when I arrived, so I played it safe (and not wisely).

Early is great because there is nobody else on the trail. However, the reason is probably that people delay their hike so they will be in time for the Ross Lake Resort boat which takes people back to Diablo through the narrow gorge of Skagit River.

Ferry Schedule:

Diablo to Ross Lake Resort: 10:30 and 14:00

Ross Lake Resort to Diablo: 11:00 and 14:30

Trip takes 30 minutes, $10 per person one-way

Quite a few deer around. Lots of woodpeckers – hard to see but I heard drumming of Northern Flickers (the loud, high-pitched cry gives it away), Downy Woodpeckers, and Hairy Woodpeckers (so rapid, they sound like an internal combustion engine).

Instead of waiting several hours, I decided to retrace my steps and have a look at Sourdough Creek trail. There is a nice waterfall at the end, but the main attraction is birds. I thought I saw a Northern Spotted Owl (see pic) but its behavior was more like a Barred Owl, so I guess it was. I also saw a female Sooty Grouse with three chicks. I’m still trying to work out why grouse don’t seem to have the maternal behavior of gathering their chicks together when danger arises. Maybe the ones in National Parks don’t see humans as dangerous.

Great hike to explore more of the recreational area around Diablo Lake. The water was low and slow enough that we could see the waterfall at the end. My watch recorded a little over 4 miles roundtrip from the Learning Center.
Parking can get busy with the Skagit Tours and some of the day camp activities sharing some of the same parking lot, but we managed to find a spot at 9:30am on a Sunday.

Beautiful trail with lots of gorgeous scenery and a stream at the top for me to soak my feet in. Views of Colonial peak and pyramid peak along the way.

Arrived at the Environmental Learning Center lot just before 10:30 on this sunny Wednesday morning, lot was less than half full, with no one in overflow. Signs at the trailhead announced recent cougar and bear sightings, but I saw nothing but birds and squirrels on my trip today. Bugs were an annoyance today, ended up with several bites, bug spray was helpful.Trail is in good condition and well marked, just one small downed tree that was easy to step over. The trail does get rocky and uneven towards the top, but the waterfall is worth it!  Was pleasantly surprised to have the trail and the falls all to myself, in fact, only encountered one hiking group on my descent. Spent my lunch break sitting by the creek and watching the falls before returning the way I came. Perfect day on trail!