For how far out it is, it's surprisingly good, but still spotty. As I recall, the signal was pretty good in the big open field by the cabins and picnic area.
AT&T had a good signal people with TMobile had a poor signal. No idea about Verizon. The park has no public WiFi.
It really depends on your carrier but some places you just wont get any
They have free Wi-Fi at the community center, and Wi-Fi for $1 at Whitney/Brinnon Gardens.
Gooey duck bar and grill. Not sure about a library. There are others along the canal too.
Hotspot on your phone if you can
Verizon has the best local coverage, with AT&T a close second. Others are pretty spottu or just don't work. Free wifi at Brinnon Community Center, north of the park on the other side of Brinnon. Also free wifi at Halfway House
I have consumer Cellular and I had to take a drive up on the hill behind the park to get a signal.
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