Pros:
Beautiful setting and landscape, full range of challenges except true water hole. Long on amenities.
Cons:
Not many - some navigation challenges maybe, and some rough tees. Definitely some lost disc risk.
Other Thoughts:
Seneca Creek has long been considered one of the elite disc golf courses in the Mid-Atlantic region, and rightfully so. The landscape is just about perfect, with the course playing over a set of gradual hills rising from Seneca Creek. The course is well maintained, can play not too long from am tees to close pin placements to exceptionally long from pro tees to far pin placements. Within its 27 holes are many of the best pure woods holes I've ever played, but also a fair number of more open holes. And finally, you need the whole range of skills here - length, right and left hooks, a precise approach game, putting to tough placements, rollers, the whole bit.
Seneca Creek is long on the amenities that make a good course great, in my opinion. Three nine hole loops that all come back to the parking lot. Three pin placements for every hole, making for excellent variety among the holes and among visits. Bright yellow flags atop the baskets to alert you to the current placement. A course map at the beginning and one excellent sign for every hole. At least one and usually two concrete tees per hole, plus yellow markers for natural pads for beginners. Benches where you need them. Rescue poles in case a cedar tree eats your disc.
It's hard to find something negative to say; some of the tees are a bit rough I suppose. A few extra tees left over from an earlier version of the course, plus some long transitions between holes, could create confusion. The holes running along the creek may be a touch odoriferous after a heavy rain. And I suppose a nice lake or a towering view of the surrounding countryside would improve Seneca, but not much.
Like Patapsco, the other elite course in Maryland, the worst hole at Seneca Creek is still better than most of the disc golf holes I've played. Really, there are no bad holes here. The true woods holes are challenging but reasonable, with appropriate fairways. Outside of the woods, the holes still feature tree hazards, including a large number of disc-eating cedar trees. The run of holes along the creek are truly picturesque in landscape and playability. While the course is lacking one hole that is a pure downhill chuck, the course does make good use of the elevation available. Overall, this course is as flexible as any I've played, going from somewhat long to really long depending on where you tee off and how the course is laid out.
Based on landscape, playability, and amenities, Seneca is definitely among the elite courses I've played; residents of the DC/Baltimore megalopolis sure have some truly distinctive disc golf course to choose from.