The most obvious solution is to skip that lot and take a walk
The lot at Walden Pond is awfully convenient if you’ve got a family that includes little kids and all the stuff they can’t carry. But it’s definitely not the only place to park if you’re willing to walk a bit. There are some pull offs on Walden Street north of Route 2 and also around the high school. Additionally, you can try to find one of the spots on Old Concord Road and off Fairhaven Road near the Lincoln Land Conservation Trust entrance. They can be hard to spot, but they’re there
But keep this in mind: If the lot is full, the beach is sure to be jam packed on nice summer days. You might want to ask yourself if that’s the spot you really want to be in. If you’re kid free or you have children that are a little older (say, around 8 years old or more), walking around the pond and finding a big rock to use as home base for the afternoon is a viable option.
Another option is to skip the pond entirely and take a walk through the 104 acres that make up Adams Woods. If you have a frisbee, bring it along as you’ll want it when you discover Pleasant Meadow in the southwest section of Adams Woods. Pay attention to which path(s) you’re taking as there are spots in Adams Woods that interconnect with the trail system around Walden Pond.