There's a nice bit of climbing at first - some of the switchbacks can be tricky. A few blind corners so be wary of runners and hikers on the trail. The majority of the descents have a nice flow, but when the trail is dry, there are several sections that can be pretty loose and gravel-like.
Need To Know
The "Creek" section following #27 Marker has a part that needs to be ridden through and on... I haven't seen water in it yet, but there are obvious signs that it does flow.
There's a nice stretch of warm-up section from the parking lot - once you cross the entrance to the housing section, the climbing starts. The climbing bits are broken into two sections and the first bit isn't that tough.. you get a bit of a reprieve and a little descent section to get your breathe back before the second part. The second climbing bit is a bit tougher, the trail narrows and a few of the switchbacks can be a bit vexing... no problem to ride down, but tougher to ride up.
Once you get to trail marker #14 the trail splits... and this loop follows the trail up for a bit more climbing, nothing tough though there is one little tech section that you'll have to climb through. You'll know you're there when you see it... watch the tree branch on the left side, it's tried to grab my handlebars more then once.
Once you reach marker #15 you'll almost be at the biggest "tech" section of the ride - again you'll know your there when you see it... it's a rack stair/step-down (personally, it's one of my favorite parts of the ride). Once past that, the ride settles into just a fun bit of riding, a couple more really short tech sections... nothing major though.
Once you reach marker #27, you'll be on the road for a bit, maybe 3/10ths of a mile at most. Once back on the trail it's a pretty easy spin back to the parking lot... a bit more climbing to do from marker #18 to #19 but that's it really. As a side note... I don't really consider this a black diamond trail, but the trail is pretty narrow, and i wouldn't really recommend you take a beginner/newbie on it, as there are parts where your bike handling does need to be on it.