One of my favorite walks is the one mile loop around Reflection Lake on the Palmer Hay Flats. You can access from the Glenn Highway exit just north of the Knik River bridge. There's a small parking area with signage for Reflection Lake.
I waddle pretty slowly and I can do the loop in under an hour. I've seen moose, beaver, eagles and squirrels along this trail. The pictures below were taking in late October, 2012. The temperatures have been below freezing, but no snow. This is sometimes the best time of year to be out. It doesn't take too many layers to stay warm and there's no mosquitoes. Those little blood suckers were horrible this summer, so it's a nice to not have to deal with them.
I like to walk the trail in the counter clockwise direction, going to your right as you start the loop.
For more info on the Palmer Hay Flats, you can visit the Alaskans for Palmer Hay Flats groups website here.