The estate, an example of the American country house movement of the late nineteenth and early twentieth centuries, was designated a U.S. National Historic Landmark in 2003.

[5] The rest of the Oldfields estate, which was given to the Art Association of Indianapolis by Lilly's children in 1967, now makes up a major portion of the Newfields campus.

[3] In addition to the home's significance as a representation of the American country house movement, Oldfields' gardens and grounds are a rare example of a preserved estate landscape designed by Percival Gallagher of the Olmsted Brothers firm.

[2] Oldfields was established as part of the Town of Woodstock, a tract of land purchased and developed by Hugh McKennan Landon and Linnaes C. Boyd around 1910 as a suburban neighborhood north of Indianapolis.

[3] The area was adjacent to the 555-acre (225 ha) Crown Hill Cemetery and the White River, and included residential lots, a reservoir, and a country club.

Additionally, muralist Douglas Riseborough was employed to update the stair hall and the loggia with murals depicting the surrounding grounds and gardens.

As industrialists and businessmen became wealthier at the turn of the twentieth century, it became increasingly popular to invest in large, country estates located outside of cities.

This formal sunken garden was located to the south of the home and was connected by a series of pathways, flights of steps, and a limestone bridge.

The landscape remained largely unchanged until Percival Gallagher of the Olmsted Brothers Firm was hired in 1920 by Landon's second wife, Jessie.

The ravine garden consists of a watercourse lined with an extensive pattern of rocks, flowers, shrubs, and trees, as well as a meandering path and bridge.

[3] The Grand Allée, or vista, at the front of the property, added an increased sense of formality to the estate, while also serving the more practical function of blocking unwanted sounds and views of Michigan Road.

A circular fountain and sculpture of The Three Graces were installed at the end of the allée, positioned in front of a line of evergreens that block the road.

Behind the elm trees on both sides of the allée, Gallagher designed border gardens with meandering paths, a multitude of flower beds, and additional sculptures.