I was looking through the top Washington courses page on DGCR and I was surprised to see a few courses higher on the list, and this one not at all, it deserves to be in the top 25 for sure, it is a very nice course that is emblematic of the Pacific Northwest.
-Tee signs are nice, give distance, par, and a map
-Baskets are like new, Some that are hard to see have flags, others you have to look around a little for, but you can find them relatively easily.
-Fairways: Typical of a wooded course, a few wide open grass field type holes, well maintained, limited to no garbage on the ground
-For an area, and a park, with little elevation, there is good use of mounds, divots, and hills here, I think it was hole 6 or 7 that was on a big mound that made putting a fun challenge
-Trees are well used, some holes are pretty cluttered around the green and you gotta play Plinko a little bit, but for the most part there are good trees
-Paths are marks with arrows, and are fairly well worn, which makes navigation less of a struggle
-water comes into play a little bit on hole 5, there is rough before it, like, right before it, if your disc goes in the water it is gone
-Mandos: added on some holes to separate other fairways, some are seemingly unnecessary
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-Tees, not clearly marked except for signs, gravel is not the best
-No benches to sit on, this is a course I played on a long driving day and it was nice to stretch out, but, a lot of people like benches to rest on
-Not a lot of variety, usually just a tunnel in the trees or a wide open bomb
-Holes 3 and 4 get really close to each other, as do 2 and 5 so you have to be really careful if you play on a crowded day

3/4 on the new shoe index
This course is pretty under appreciated for what it is. I've played some course that seem to get more love even though they aren't as good as this one, if you are willing to make the drive, stop by!

-Great mix of woods and open holes
-As summer moves on the foot traffic makes even the more challenging holes decent for finding errant discs
-most of the course in in woods which means "shade" in the hot months
-Beautiful and challenging

-Spring and early summer the course is severely overgrown both in the woods and open making the possibility of losing discs very real.
-a lot of blackberry bushes
-This area attracts a lot of shady characters. I've never had issues but talked to a guy who's vehicle was broke into. Park in open and don't leave things in sight.
-hole 4 isn't on course map.

This area is next to the river and as such get affected by flooding so winter and spring play can be interesting. Hole #4 doesn't show up on the course map but I have the "Udisc" app on my phone which it does show on it's map. This is a fun challenging course that changes quite a bit through the year. If you play it in March and then again in August you will most likely play some of the holes differently.

Nice park. Good mix of wooded and unwooded holes.

The brush along the fairways is thick but manageable. I think hole 6 is missing? And some of the tee pads are just horrible. I don't mind gravel tee pads as long as they are kept up?

Overall, I really liked this course. It was fun, despite looking for discs, which just makes me want to get better so I dont go in the tall or thick brush, I will most definitely be playing this course a lot more

Arlington is a easy to navigate course, there's so much rough you have to follow the trail, and there are arrows on the trees near the baskets to show the next tee. It's got a nice mix, very technical at times. Distance varies, nothing too short (Hole 4 is the shortest one but interesting, there's a row of 5 trees in front of you, you can just zip it thru straight up or go around on the open left side.). The fairways are clear but can be very narrow at times, and be very careful to stay out of the rough and suggest good spotters before you throw. Trust me you WILL go into the Rough more than once in a round. Baskets are nicely placed. One basket No. 7 is on a large molehill, watch for roll aways. Myself and a few masters got a couple birdies in this course, and they didn't come easy.

Blackberry & the Rough. In the summertime, if your disc goes into the rough you can kiss it good bye. Please do Spot every hole, even the open holes w/ tall grass. In the winter, it's manageable but the tees and trails get very muddy. Come prepared. I agree w/ JR Stengele about the arrows. Hard to tell if they're for the next Tee or if it's a Mando.

It's wild, flat and strongly wooded. Mostly cottonwood and various trees. Sometimes the grass is tall. Runs by a large fast moving river. There's 4 open meadow holes that let you air it out for 400 yards. Personally, I find these the hardest. Be lucky to get a bogey on each one. There's no OB in this course, unless you lose your disc in the blackberry or the river and have to take a drop. No real water hazards. Arlington is a wild and beautiful course and defintely worth visiting.