Difficult - uphill all the way. Only people in reasonably good shape should attempt this hike.
Miles from Anchorage
25; on the Seward Highway along Turnagain Arm
This is a really great hike! It was so cool to get aerial views of places that I've hiked at ground level: Turnagain Arm, Indian Valley, Ship Lake Valley, and Bird Creek. The scenery is incredible and stunning, but boy, you are really going to have to work to get at them. The first 3 miles are very tough. Up and up and up. You see a ridge and think you're almost there. Then you get to that ridge and there's another.
Most guidebooks break this trail into 2 sections. The first is the initial peak at roughly 3,500 feet. Most people stop here which is fine, because you're really exhausted by then. But it's really worth the effort to go the extra miles and walk along the ridge up to the Overlook into the backcountry; an elevation of roughly 4,700. Most of it is pretty easy except the last part where there is a short ascent. Plus I have to say it's really cool to walk along the spine of a mountain.
My suggestion is to start this hike early and give yourself the entire day. Bring a lunch, etc and plan on being up there for 6-8 hours. If it's an especially nice day, you'll be glad you did. Pace yourself for the initial haul, then leisurely head to the Overlook. Bring a map so you'll be able to identify the valleys and peaks you'll witness.
I really want to reiterate what a great hike this is! When I did it, my allergies were miserable and I really suffered while I was up there. Yet, it was one of the coolest hikes I've done in Alaska. This is probably one of the best hikes for viewing the Chugach Mountains.
There are no water sources, even at the trailhead. Bring an adequate supply.
Needless to say, be very careful going down. It is quite steep.
Use the the actual ridgeline when heading to the Overlook, then use the trail along the side to get back. You'll avoid a lot of elevation that way.
This is a very popular mountain for racers and you'll see them on your way up. To this day, I still can't believe people actually get enjoyment out of doing something like that.