From I-287 use Exit 36A [from north] or Exit 36 [from south] and find way to 353 East Hanover Avenue, Whippany, NJ. GPS coordinates: 40.805500,-74.451900].
A former estate, now a county park, the arboretum has nature trails and is known for its rose garden and other floral displays.
The Arboretum is traversed by a 1.7-mile-long blue-blazed spur of the Patriots' Path, which leads from the main stem of the Patriots' Path through the Arboretum and continues to the Acorn Hall historic site and to the Ford Mansion, which served as Washington's Headquarters during the Revolutionary War. The 0.6-mile Yellow Trail loops around the remote western area of the Arboretum, the 0.4-mile Red Trail curves around the southern corner of the Arboretum, and the 0.3-mile Orange Trail offers a short, easy stroll at the eastern end. There are also short Purple, Teal and Green Trails, which serve as connectors and can be incorporated into loops.
From the main parking area, a 1.3-mile loop can be formed, using the Red, Yellow, Blue and Purple Trails.
An excellent map of the trails in the Arboretum is available from the Morris County Park Commission website, www.morrisparks.net.
What is now known as the Frelinghuysen Arboretum was once the summer estate of George Griswold Frelinghuysen and his wife Sara Ballantine Frelinghuysen. Designed by a prominent firm of architects, it was built in 1891 in the style of an English country estate, and the estate was planted with many trees and shrubs considered essential to an English-style landscape. The mansion and grounds were named Whippany Farm. The Frelinghuysens' daughter, Matilda, inherited the 127-acre property and, in memory of her parents, bequeathed it to Morris County in 1969 for use as an arboretum. It was dedicated in 1971.. Visit the Friends of Frelinghuysen Arboretum web page for events and activities.