AS American canals go, the Erie, which famously linked Buffalo to Albany in the early 19th century, gets all the glory. But at its peak in the 1860s, the V-shaped Delaware and Raritan Canal running through central New Jersey was no pipsqueak transportation system. One year it even outdid the Erie in tonnage carried. And since the early 1970s the narrow waterway has been the centerpiece of a 70-mile-long state park popular with bikers, walkers, fishermen and boaters.

Biking along the banks of the canal, with its old bridge tender’s houses, locks and stone bridges, is easy on the heart rate and the hamstrings. The blessed absence of hills and the abundant greenery along the banks — including shady stands of silver maple, ash and birch — makes it bearable even on the most scorching summer day. And if you’re fortunate enough to join a guided tour led by Linda and Bob Barth, your imagination will be stirred by the ghosts of laborers who built this navigational wonder by hand.

The D&R, as it is commonly known, opened in 1834, nine years after the official debut of the Erie Canal, to speed the transport of coal from northeastern Pennsylvania to New York City. The main canal ran from the Delaware River at Bordentown, N.J., to the Raritan River in New Brunswick, while a feeder canal stretched from Bull’s Island, just upriver from Stockton, to the main canal in Trenton. The feeder was built to supply water from the Delaware to the main canal, though it was later used to transport goods as well.

Boats and barges on the canals were pulled by mules, followed later by steam-powered vessels. By the late 1800s, though, competition from the railroads drastically reduced traffic, and the canal was finally closed after the 1932 season.