https://www.njhiking.com/columbia-trail/ | http://morrisparks.net/index.php/parks/columbia-trail
The Columbia Trail, is a 16.5-mile flat, multi-use, linear trail with natural and gravel tread. The trail spans segments of both Morris County (100.4 acres) and Hunterdon County. The Morris County section of the trail is 8.5 miles and runs through Washington Township to the border of Hunterdon County. The Hunterdon County section of the trail is 8 miles and ends in High Bridge. The trail can be used for a variety of activities, including horseback riding, bicycling, hiking, snowshoeing, and cross-country skiing.
https://www.traillink.com/trail/patriots-path-(nj)/ | http://morrisparks.net/index.php/parks/patriots-path
If you enjoy recreational activities, such as biking, horseback riding, cross-country skiing, jogging, walking your canine companion, and hiking, Patriots’ Path is the place to visit. Comprised of 55 miles of main trails and 35 miles of spur trail located on 291.9 acres, Patriots’ Path is a trail system of hiking, biking and equestrian trails, as well as green open spaces. It links several federal, state, county, and municipal parks, as well as watershed lands, historic sites, and other points of interest throughout Morris County. Since much of the Path lies along the corridors of the Whippany and Black Rivers and the South Branch of the Raritan River, you can always enjoy a trail along the water. The Black River and the South Branch of the Raritan River are two of the most pristine trout-production steams in the state. This trail extends across the entire County of Morris from Essex County to Warren County.
Liberty Water Gap Trail
The Liberty-Water Gap Trail is envisioned to connect Liberty State Park in Jersey City, NJ with Delaware Water Gap, PA. Efforts are underway to extend this trail into Pennsylvania via the Portland-Columbia Pedestrian Bridge, serving as a new recreational connection between many existing trails in the Delaware Water Gap region.
East Coast Greenway
Travel through the bustling urban areas of Trenton, New Brunswick, Newark, and Jersey City but also a surprising share of quiet, traffic-free paths, including the D&R Canal Towpath.
The Appalachian National Scenic Trail (AT) extends along the spine of the Appalachian Mountains from Springer Mountain, Georgia, to Mt. Katahdin in Baxter State Park, Maine. Of the 2,174 miles of trail, 28 miles are within the Delaware Water Gap National Recreation Area. Whether hiking for a couple of hours, for the day, or for the entire length of the trail, the AT provides opportunities for majestic views, wildlife sightings, and hiking challenges.
September 11th National Memorial Trail
The September 11th National Memorial Trail is a 1,300 mile system of trails and roadways that are a symbol of resiliency and character that links the World Trade Center in New York, the Pentagon in Washington D.C., and the Flight 93 Memorial in Shanksville, Pennsylvania. It serves as a tribute to the fallen men and women who perished on September 11, 2001.
You can view even more outside trails here.