Colonnade MTB Park in Seattle

I watched the documentary called 'Pedal Driven' the other day and was impressed with the video footage of a mountain bike park under a highway overpass in Seattle. I was wondering if anyone on here has ever ridden it? How was it? Is it a good use of space? Could you see Chicago benefitting from something like this? Is there anywhere in Chicago that this could be done? I remember a friend telling me that there is a skate park under a bridge somewhere, but this type of park is much different than a skate park.

The Yelp reviews claim that the space is sheltered from the weather so it can be used year round. The biggest complaint is that there isn't enough beginner stuff.

Here are a few links to information about the park:

http://www.seattle.gov/parks/park_detail.asp?id=4446

http://www.yelp.com/biz/i-5-colonnade-mountain-bike-park-seattle

I looked for a video clip of the footage I saw but couldn't find one.

(note I also looked for a thread about this and didn't see any)