You can pretty much do all the things at Mount Blue State Park in Weld.
You can wake up early for a swim in the lake (and possibly be the only person there). You can climb Mount Blue, stopping to peek inside the collapsing cabin, before sweating up to the summit and mounting the steps of the observation tower. Or hike nearby Tumbledown and scramble over rocks and then plunge yourself into the pond at the top. You can rent a kayak and paddle out to the center of Webb Lake on a calm evening for views of Tumbledown and Mount Blue (and think to yourself, “I hiked that”). And you can set up your tent at the campground, light a fire, and spend a few nighttime hours reading a book by the light of your headlamp. Nice, right?
More Hike & Swim: 20+ trail hikes that include a refreshing swimming hole dip
Camp

The campground at Mount Blue State Park has 136 wooded sites (enough trees to separate the sites, but not so much that you can’t easily see/hear your neighbors). There are campgrounds with more privacy, but the other perks at Mount Blue State Park (ie, THE LAKE) are an easy trade. Besides, it’s nice to see other humans having a grand camping time, too.
It’s a family-friendly campground, and there were kids biking down the campground roads and gathering wood to build things when I was there last week. But even on a weekend in early July, the campground seemed half full and still easy-going and quiet enough to feel like a getaway, even if your neighbors were visible through the trees.
FMI: www.maine.gov (2017 camping rates are $20 resident/$30 non-resident per night)
Swim

And then there’s Webb Lake. The campground is right on the lake, and there are trails leading down to the beach (there’s a parking lot at the beach, too, for folks who want to drive right to it). From my site, it was an easy five-minute walk. When I wandered down there at 8 a.m. for a swim, I was the only person there. It was splendid. There’s a roped-off swimming area, sandy bottom, and views of the mountains. Plenty of grass to sprawl out on, too.

Paddle

You can rent a kayak or canoe for $4 an hour. Register at the ranger station (it’s first come, first served) and they’ll give you a paddle and PFD. One evening I was there was insanely windy, so rentals were on hold, but on another evening, I paddled on the calmest waters, following the shoreline for a while to watch fish. From the center of the lake, out in front of the campground, you can get amazing views of Tumbledown and Mount Blue, as well as Little Jackson, .
Blueberry Mountain, and others.

Hike

Mount Blue
Mount Blue is a short drive from the campground (Mt. Blue State Park is divided – lake access and the campground are off West Side Road on the southwest side of Webb Lake. Mount Blue and Center Hill hiking are off Route 142, northeast of the lake. See this map). It’s a 1.6-mile hike straight up Mount Blue. I took a number of breaks to catch my breath, and the collapsing cabin about 1/3 of the way up was a nice opportunity to explore and take a breather. The trail gets decidedly more bouldery and fun the higher you go.

At the summit, the views are pretty spectacular. There’s an observation tower you can climb (at your own risk, of course). Not one for heights, the wide stairs and railings made this tower easy to climb and loiter on. Loads of wildflowers up here, too
FMI: www.mainetrailfinder.com/trails/trail/mount-blue-state-park-mount-blue-trail

Tumbledown Mountain
Another stupendous (and popular) area hike is Tumbledown Mountain, also just a short drive from the campground. There are a few trail options to choose from: The 1.9-mile Brook Trail will take you straight up to the pond near the summit, where you can lounge near the water or get in for a swim. (With all the sweating you’ll do on your way up, it’ll feel great to cool down in the pond.) Or take the Loop Trail for added challenge (in the form of steam crossings, rock scrambling and Fat Man’s Misery – a narrow fissure in the mountain you’ll have the pleasure of climbing through).

I opted for the Brook Trail, which was well trafficked on a Tuesday afternoon. Plenty of boulders to scramble over, especially nearer the top, and wow, that pond is a stunner. Lots of hikers wore their suits the whole way – some of us had fun changing in the shrubs. The water’s chilly, but chilly is really “refreshing” when you’re sweating your brains out from the hike up, right?

The hardest park about hiking Tumbledown is having to pull yourself away from the edge of the pond to head back down. Do I wish I brought a tent up there and extra food so I could just live there forever? Yes. But heading back to a campfire back at Mount Blue State Park was pretty swell, too.
FMI: www.mainetrailfinder.com/trails/trail/tumbledown-mountain-and-little-jackson

Mount Blue State Park
Webb Lake campground/beach: 187 Webb Beach Road, Weld
Camping: $20 resident/$30 non-resident per night (check the current fees)
FMI: www.maine.gov
PDF of map and info: www.maine.gov/mtbluetumbledownguide.pdf
Mount Blue: www.mainetrailfinder.com/trails/trail/mount-blue-state-park-mount-blue-trail
Tumbledown: www.mainetrailfinder.com/trails/trail/tumbledown-mountain-and-little-jackson