New River Trail State Park in Virginia is a 57-mile long trail that follows the New River along an abandoned railroad bed. This provides a gentle slope with no steep hills that is perfect for a loaded bike! There are multiple trailheads that provide parking (with a $5 fee) for access to the trail at Galax, Fries and Foster Falls.
The road surface is a wide, hard-packed dirt trail with occasional loose rocks and branches so a cross bike, hybrid bike with knobby tires or mountain bike would all be excellent choices. The bike will need to accommodate all your gear if you choose to stay overnight.
Camping and cabins are available and can be reserved in
advance. There are restrooms and water along the trail and a few food options in Galax and Fries.
Set out all the items you will need for your overnight trip and make sure they will all fit on your bike. Choices include a rack with panniers, saddle and handlebar bags or a backpack. I like the Arkel Dry-Lites Panniers, at 540 grams, they are the lightest waterproof saddle bags around.
We chose to park at Foster Falls, load up the bikes and ride to Galax (24 miles), then camp overnight at Cliffview Campground. On the second day we road to Fries for extra mileage and then back to Foster Falls (35 miles). The route to Fries was a 5 mile out and back add-on, a very scenic section were the river widens that I highly recommend.
For more information, checkout http://www.dcr.virginia.gov/state-parks/new-river-trail#general_information