Henry David Thoreau’s sojourn at Walden started a long tradition of people coming to the pond and its surrounding woods for recreation and inspiration. The emergence of Walden as a public park was in keeping with the belief that nature is meant to be enjoyed by people. "I think that each town should have a park…a common possession forever, for instruction and recreation," he wrote in a 1859 journal entry lamenting the deforestation that had taken place around Walden. "All Walden wood might have been preserved for our park forever, with Walden in its midst."
In the latter part of the 19th century, numerous projects were undertaken to make Walden Pond a public destination for recreation. The Fitchburg Railroad, which had laid tracks past Walden the year before Thoreau took up residence there, built an excursion park on the shore at Ice Fort Cove in 1866. The facilities were mainly used for fund-raisers, festivals and groups. The park included concessions, swings, bathhouses, boats, baseball diamond, a hall for dining, dancing and public speaking and a cinder track for runners and bicyclists. The park burned down in 1902 and was never rebuilt.
The automobile brought increasing numbers of visitors to Walden Pond. The Town of Concord began offering swimming lessons in 1913 and bathhouses were built in 1917. Summer visitation had risen to 2,000 visitors a day even before the bathhouses were built.
In 1922, the Emerson, Forbes and Heywood families granted approximately 80 acres surrounding the pond to the Commonwealth of Massachusetts with the stipulation of "preserving the Walden of Emerson and Thoreau, its shores and nearby woodlands for the public who wish to enjoy the pond, the woods and nature, including bathing, boating, fishing and picnicking." Middlesex County was given the responsibility for management of the reservation. In the summer of 1935, some 485,000 people visited Walden Pond, with Sunday crowds numbering as high as 25,000 visitors.
In November of 1945, the centennial of Thoreau’s move to Walden, Roland Wells Robbins, an amateur historian and Thoreau enthusiast, discovered and excavated the foundation of Thoreau’s chimney. In July of 1947, the Thoreau Society dedicated the inscribed fieldstone that marks the hearth site today. In 1965, the National Park Service designated Walden Pond as a Registered National Historic Landmark.