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Is peninsula more crowded than devils lake?
I never quite understood why Russian seems to be the predominant language you’ll overhear at devils lake and why there’s always buses full of Japanese tourists there.
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It's pretty busy, but I'd wager Devil's Lake is the busiest in the state.
It's close proximity to Milwaukee, Madison, and being right next to the Dells really increases the numbers. It's easy for them to get on a bus, hit 94 and get there in 90 minutes.
Peninsula is right in the middle of Door, so you're less likely to get a bunch of day trippers from a large metro area. However, the camping reservations are usually booked up months in advance.
Just my experience, but top 3 busiest state parks are probably:
Devil's Lake
Wyalusing
Peninsula
In no certain order. If you want to camp at any of those on a summer weekend, you need you start trying to reserve spots 8 months out, or earlier.