Umbagog is awesome! Contact the NH division of Parks and Rec. for camping info. There are remote sites accessible only by water as well as a drive up camping area. If you camp remotely, I highly recommend getting an air horn and a can of pepper spray for the bears. We had a long night with a bruin that wouldn't leave last summer. I'd chase it into the woods, and it kept coming back. I'm to blame...I had a cooler full of food that was awfully tempting to it. I'd like to take this moment to thank the five rangers who checked me into my site who neglected to mention that bears had been on a rampage last summer, raiding campsites. Apparently it was the worst year any of them could remember. A warning would have been nice. Oh well...it was my fault anyway...I should have been better prepared.
The fishing is spectacular for smallmouth. The lake is full of them, and they are big. If you are bored by soaring eagles, bass that destroy poppers and lazy paddling, you can venture to the mouth of the Rapid River at the northern end of the lake for some fabled brook trout fishing. Both Maine and NH licenses are okay in the lake, but you need a Maine lic. to fish the Rapid.
Here's a great site for info:
http://www.nhstateparks.org/ParksPag...g/Umbagog.html
Have a blast!