I am sure it wasn't the first time, but the most memorable is the time in 2001 that we were camped on Gaskin Lake in the BWCA.  That campsite had a nice place to put the tent that was elevated, but still very close to the water.

The beaver was busy all of the time we were there, right in our view, even from the small "window" at the back of the tent.  Hearing the slaps at evening and in the night was something that would wake me up, but not alarm me, as we had seen him/her traveling back and forth during the day as well.

I love that sound.

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