Portland's 4T Trail

Go multi-modal by taking this loop around Portland's West Hills.  Starting at the Oregon Zoo, hike 3-4 miles in thick green forest, including going over the top of Council Crest with great views on a clear day, then end up over at OHSU's hospital, where you can catch the tram down to the waterfront terminal.  From there, it's a short hop over to the streetcar trolley that you can take up to downtown and catch the MAX train back to your starting point.  There are great options to stop somewhere along the way for a treat or a lunch.  Feel free to start at any point along the loop, but I have generally enjoyed taking the train in to the loop so you don't even have to worry about paying for parking anywhere.  For the price of a Tri-Met day pass, you can have a fully self-contained adventure in urban exploration.  I've taken Webelos den's on this hike a few times and it's always a hit.