Walden Pond Trail is a standout hiking destination in Concord, Massachusetts, covering 1.7 miles with 80ft of elevation change. Stats: 1.7 miles, 80ft gain, Easy. Type: Loop. Surface: Dirt. Time: 1 hour. Fee: $15 parking. Dogs: Yes. Permit: No. Wildlife: deer, foxes, herons, painted turtles. Best seasons: Thoreau's famous glacial kettle pond circumnavigation. Pack water, layers, and appropriate footwear. Conditions vary across Massachusetts. Leave No Trace: stay on trail, pack out all waste, respect wildlife.