September 18, 2017
This is my local trail and where I learned--and continue to learn--to ride mountain bikes. This is my second season, and I'd consider myself a beginner-intermediate rider. I just started riding mountain bikes last summer and have only been to a few different places to ride, but I rode BMX as a kid and have been riding dirt bikes and other motorcycles since before I remember.
That said, I find 909 to be a great set of trails. It's a large park for the area with quite a few more trails than I am currently in shape to do in a day. As others mentioned, you won't get lost here thanks to the fire road that runs through the center of the park. But there are a ton of trails--and after two summers, I'm still finding new ones.
I usually start my rides out on Mercury and Mustang, both of which feature some great technical turns and fast but comfortable downhill straights. Tango is my favorite trail, with a long, fast downhill section and some excellent technical features. Byk Hed is fantastic and long, with a medium climb up from the Taconic Parkway entrance and a ton of technical riding and some nice, fast sections. Fong's Way is a hefty climb that's definitely worth the effort. It's the most technical trail that I've ridden at 909 and one of the most rewarding. There are also a few trails that feature drops and very steep downhill sections that are simply outside my current skillset. As such, I haven't ridden them much and can't offer any details--but I look forward to the day I'll consider them fun instead of terrifying.
For me, the downsides to 909 are too many steep climbs--I don't mind some but you really have to climb here to have a good time. (But the payoff is in long trails with solid fast sections.) The fire road is great for getting to other trailheads quickly (and getting back to your car when your legs are shot), but there are sometimes cars and the occasional dirt bike that drive too quickly without enough caution. You also have to watch out for hikers and dogs at this park. (Mine among them.) But they are relatively few and far between. Lastly, as others mentioned, the trails aren't very well marked, so even if you don't get lost, you might have trouble planning an exact trail run without some prior experience on the trails.
All said, this is an excellent park and one that's worth making a trip to. The trails are well maintained and the people who ride here regularly are all friendly in the parking lot and courteous on the trails. And even if you show up and the parking lot and the sides of the roads are full of cars, once you're on the trails, you may not see another soul.