The Lowest Mountain Range In The United States

The highest point in New Jersey's Watchung Mountains is High Mountain in the town of Wayne, at just 879 feet above sea level. That makes the Watchungs one of the lowest named mountain ranges in the United States, lower even than California's Sutter Buttes, which are often called the world's smallest mountain range. There is no official US ranking of mountain ranges by height, and the US Geological Survey does not set a minimum elevation for what counts as a mountain. But measured by its highest summit, no well-known named range in the country sits lower. The Watchungs are not much to look at on a map, yet they were built by some of the largest volcanic eruptions in Earth's history, and they helped shape the course of the American Revolution.

Three Ridges Of Ancient Lava

The Watchungs are three long, parallel ridges that curve for about 40 miles (64 km) through northern New Jersey, known as the First, Second, and Third Watchung Mountains. Each ridge is made of basalt, a dark volcanic rock, from a separate set of lava flows that poured across the region roughly 200 million years ago, in the Early Jurassic period. At the time, the supercontinent Pangaea was splitting apart, and molten rock welled up through cracks in the stretching crust. The First Watchung formed from the oldest flow, called the Orange Mountain Basalt, and the Second from the younger Preakness Basalt. Over millions of years, the softer sandstone and shale around the lava wore away, leaving the tougher basalt standing as ridges. The Passaic River still tumbles over that rock at the Great Falls in Paterson, now protected as a national historical park.

How Low Is Low?

Most of the Watchungs are even lower than their high point. According to the New Jersey Geological Survey, the First and Second Watchung ridges reach about 660 feet (201 m) near Verona, with a valley about 300 feet lower between them. The range's highest summit, High Mountain, rises in the Preakness Range, a northern section of the Second Watchung. From its rocky top, hikers can see the Manhattan skyline about 20 miles (32 km) to the east. Despite their modest height, the ridges rise sharply from the surrounding lowlands, which is why early settlers gave them names like the Blue Mountains and the Blue Hills.

George Washington's Hideout

The Watchungs mattered during the Revolutionary War. George Washington's Continental Army camped behind the First Watchung at Middlebrook in 1777, and again in the winter of 1778 to 1779, using the ridge as a natural wall between his troops and British forces in New York and on the plains below. From a rocky lookout on the ridge, now Washington Rock State Park in Green Brook, Washington could watch British troop movements across the countryside. The ridges also kept the British from easily reaching the army's supplies and its encampments farther west at Morristown.

Quarries, Parks, And Trails

The same tough basalt that built the ridges made them valuable. Known locally as trap rock, the stone has been blasted and crushed for gravel and road stone for generations, and active quarries still cut into parts of the range. Much of the rest is now protected parkland in one of the most densely populated parts of the country. Union County's Watchung Reservation, South Mountain Reservation in Essex County, Garret Mountain Reservation in Passaic County, and High Mountain Park Preserve in Wayne all keep large stretches of forest open to the public. Trails in these parks follow the ridgelines and cross rocky outcrops of basalt, and hikers should expect steep, uneven footing in places, especially on wet rock.

Small Ridges With A Big Story

The Watchungs will never compete with the Rockies or the Sierra Nevada for height, but few ranges pack so much into so little elevation. Their basalt records the breakup of a supercontinent, their ridgelines sheltered an army through two hard winters, and their forests now give one of the most crowded corners of the country room to breathe. Measured by summit, they are the lowest range around. Measured by story, they stand much taller.