The Walnut Park Company established this park with the purchase of a barren hilltop in 1854. Following the construction of a reservoir atop the hill in 1858, landscape gardener B. Munn laid out the park’s first circulation system. In 1870 New Britain’s park commission hired the landscape architecture firm Olmsted, Vaux & Co. to design the park, shortly before purchasing the site from the Walnut Hill Company, along with 56 acres for its expansion. The firm’s design resulted in a richly vegetated landscape comprising Walnut Hill and a meadow, called the Common. The firm’s plan for a monument near the reservoir was realized in 1928 with the installment of Harold Van Buren Magonigle’s World War I Memorial. In 1929 James Burke, the city’s gardener, planted a rose garden that was later demolished. In 2010 the Friends of Walnut Hill Park Rose Garden planted a new garden on the grounds of the reservoir, which had previously been infilled.
The 98-acre park still reflects Olmsted, Vaux & Company’s original design. Circulation routes laid out by Olmsted connect the park’s entrances to the Common and Walnut Hill. Encircled by an elliptical drive, the meadow holds several recreational fields, in keeping with Olmsted’s plan. Sharing the lawn are tennis courts, a playground, a bandshell, and a memorial garden. Roads ascend the hillside to reach an oval lawn framed by two colonnades on its minor axis. Encircled by rose bushes, the lawn is quartered by paved pedestrian paths that meet at a single-tier fountain. The memorial, which is located to the north on a perpendicular axis, comprises a 90-foot-high Art Deco obelisk. The lawn’s formal entrance, a stone terrace featuring a flagpole and a memorial to female veterans, is to the south. Behind the monument, steps built by Magonigle, and shaded by trees planted by landscape architect Arthur Brinckerhoff, descend the hill reaching a brick-paved plaza. The plaza’s walls are embedded with plaques describing the park’s history. Walnut Hill Park was listed in the National Register of Historic Places in 1982.