Yes. It’s worth it and bigger than you think.
Park near Northern Exposure and do this:
Join Norm and get inspired for your next workout
www.strava.com
That's a 2 hour ride and doesn't hit a big chunk of the park. You can easily get 3 hours here. The Northern Exposure loop should drain well. The other parts are hit or miss but it's so dry right now I think it'll be fine.
Fair warning - when I went last year in August it was clearly not being maintained as well as the last time I had been there. Trees down, some features eroding away. I may have hit it in a bad time when the TM efforts were struggling to keep up. It was still a good ride.
Let us know how it goes. I am likely going to hit it on my way to/from MA in a few weeks. Hopefully stuff has been cleaned up a bit.