Quarry Pond Campground

As others have said, the planes are very loud. I think I started getting used to them after a few days but if you're looking for quiet, keep that in mind.
The sites are very shady and private. I stayed in the Quarry Pond campground and found it to be somewhat tight. I don't think I'd want a 40 ft RV here. The roads are a bit narrow with low hanging branches and the back in sites were tight to get into.
There's great hiking trails right off the campground. The only downsides are the noise and also lack of internet/OTA.

Cell reception:
AT&T - 2 bars LTE - 4 Mb down and 2 Mb up (with booster)
T-Mobile - nothing
Verizon - 2 bars LTE - 1.30 Mb down and .25 Mb up (with booster)
Without the booster I got nothing on any of those 3 carriers.
I noticed as I walked around, that other places in the park seemed to have better reception.

50amp + water but no sewer. Dump station onsite. This is a great state park with a really good vibe and the trails and atmosphere more than make up for the plane noise.

This is a beautiful state park, right at the northern tip of Whidbey Island. The campground here is wonderful.

Everything about this place says, "Camp here!" That is, until the EA-18G Growlers from nearby Whidbey Island Naval Air Station scream by at extreme low altitudes. We were there for three nights and every single night, we were serenaded by these jet jockeys from roughly 8:00pm to midnight. At low altitude. It was so loud we could not even be heard by shouting at each other. It's even possible they damaged our hearing. It was truly that bad.

This is not to say that you will have the same experience. Their flight patterns and times vary, and are never announced for military reasons. We have friends who stayed here for several days and said they never heard any jets. We, on the other hand, had an awful experience with the noise. So, your experience may be better if you camp here. It's a crapshoot, and we wish you the best! We, however, will camp elsewhere on Whidbey next time we visit the island. Perhaps Fort Ebey or Fort Casey!

We camped in the Quarry Loop, across Route 20 from the park. This loop is quite nice, with plenty of trees, shade, etc. However, the streets in this loop are gravel and throw a ton of dust into the air with each passing vehicle. Our site, #361 is very nice and easy to park in with an RV, but it has streets on either side and thus a double-helping of dust. Traffic volume inside the campground wasn't an issue, but the dust was annoying. Oh, and when the jets weren't overhead, we heard plenty of road noise from our site. Camping loops inside the park have paved streets and thus less dust and are farther from Route 20.

We definitely recommend a visit to this park. There are nice easy hiking trails everywhere, it's a great place to ride your bike, there's plenty to see and do, and the scenery is absolutely beautiful.

There are two beaches, West and North.

At West beach you can brave the surf to swim in the ocean, or turn around and take a pleasant dip in Cranberry Lake at a lovely sandy little beach. You can also rent a kayak, canoe or peddle boat and take a spin around the lake. There is plentiful parking and they have plenty of picnic tables. Also a great place to watch the sun set. Bring a sun shade and make a day of it!

At North beach you can see the Deception Pass bridge from below, watch the currents push through Deception Pass, perhaps see a bald eagle fishing, and maybe even see a marine mammal (seal or sea lion) sunning on the gravel. It's also an easy hike up to the bridge, which you can easily walk across to enjoy maximum scenery. The hike to Goose Rock summit from the south end of the bridge is particularly nice, with great views from the top to the south and east.

Verizon signal in the park is pretty much non-existent. We were occasionally able to squeeze out some 1X, and on rare occasions a little 3G. Once our phone was even welcomed to Canada, so be careful that you don't accidentally do some expensive international data roaming. Oak Harbor, with plenty of groceries, 4G and wi-fi hot spots, is 6 or 7 miles south.

For more details and photos, see our blog post under the Blog tab above.