Several miles of walking trails lead through hardwood forest up to the Princeton ridge and the headwaters of a tributary of Harry's Brook.

It contains wetlands, frogs and salamanders, and over 60 species of native trees and shrubs, along with wildflowers, rare birds, and diabase rocks containing magnetite.

After storms blew down a pine forest, the Friends of Herrontown Woods created a Botanical Art Garden ("Barden") with sculptures, found objects, and over 150 species of native plants.

[1] The first 81 acres (33 ha) of the arboretum were donated to the Mercer County Park Commission in 1957 by internationally renowned mathematician Prof. Oswald Veblen (1880-1960) of the Institute for Advanced Study.

In 2019, through the initiative of the Friends of Herrontown Woods, 7.5 acres of Windy Top homeowners association land was donated by the developer.