Warren County Natural Resource Areas

Brass Castle to Marble Mountain

Story & photos by Robert Koppenhaver

In addition to New Jersey's extensive State Park and Wildlife Management area holdings, county, municipal and private entities provide broad tracts for public use. The park commissions in Morris, Somerset, and Hunterdon counties manage thousands of acres for recreational use. While Warren County does not provide an official network of "improved" parks, there are municipal parks and several trail networks known as Natural Resource Areas (NRAs). Similar to the state-owned WMAs, they are minimally improved tracts of land reserved for passive recreational use by the public. Though not well-known, these places provide pristine destinations for family jaunts, hikes full of historical fabric, even the excitement of cave exploration.


West Oxford Mountain Natural Resource Area

Located just south of Oxford, between Route 31 and Mine Hill Road, finding the main trail at West Oxford Mountain can be a bit tricky. It starts a short distance into the woods across Academy Street from the Oxford Rescue Squad building.

While West Oxford Mountain offers features for nature watchers, photographers, and hikers, its most intriguing feature is its involvement in the history of the local iron industry. As you wander into the woods from the parking area, you will notice various remains of the mining that once took place on this tract. An old railroad bed, wooden cistern, and small brick structure with a rusty bolted door are all that is left of the operation that took place well over a hundred years ago. Old maps show that the Staley mine operated on this tract, opened and closed before 1868, according to one internet source.

From here a narrow old lane heads up the mountain in a southeasterly direction, probably also a remnant of the mining operation. In fact, the old map shows that the Staley mine followed the same line as this old road does for about 1700 feet. Look around and you will notice much evidence of how the ground was disturbed by the mining. A few hundred feet off to the east is an old reservoir, possibly also part of the mining operation, surrounded by a low concrete wall, fed by a spring enclosed in an old rock-lined wall.

Further up, you will come upon an intersection of mountain lanes. In the northeast corner of the intersection a couple of old depressions or shafts are completely fenced off, warning you to stay back. Although the old map shows no indication of these depressions or shafts, they are located above the Staley mine which continued another 400 feet or so southeasterly. The map gives no indication of the depth of the mine below the lane here.

Near the fence you might notice a talus pile, the rocky remains that were deposited here after blasting them out of a shaft. That this talus came from an iron mine is clearly indicated by the rusty appearance of much of the broken rock in the area. Extreme care must be taken here and absolutely no attempt should be made to enter the fenced off area.

Continuing up the old lane will lead you to the top of the mountain and the borders of the NRA. This route and a couple of others add up to just over a mile of trails. The trails are fairly wide and are appropriate for family use, the elevation gain being about 360 feet. The entire area is reforested with hardwoods.


Marble Mountain NRA

The Marble Mountain Natural Resource Area is located on the southwestern end of Marble Mountain about a mile north of Phillipsburg. The Highlands Trail will eventually lead from here along more than 150 miles of trail to the Hudson River at Storm King Mountain in New York. Although only a short portion of the Highlands Trail lies within the Marble Mountain NRA, some determined hikers have already found their way along much of the proposed route for some miles northwest of here, hiking from here along Scotts Mountain to Merrill Creek Reservoir, Buttzville, then northerly along portions of Jenny Jump Mountain and beyond.

The trailhead for the Highlands Trail is located on the River Road (County Route 621) one mile north of the intersection of Hillcrest Boulevard and North Main Street in Phillipsburg or slightly less than a mile south of the intersection of Marble Hill Road and CR 621. Near the parking area a sign designates this as the Marble Mountain Natural Resource Area. Crossing the road from the parking spot, you will see that the trail heads on a diagonal up the side of the mountain, climbing along the slope which drops sharply off to your left. At places the drop is so sheer that you cannot see the river road or railroad tracks below.

The trail forks to the left and right. Heading to the left will keep you on the main trail, but taking the trail to the right will lead you to the "Ice Cave". After a few hundred feet you will pass a very large pile of loose rock on your left. Someone has spent a lot of time piling some of the loose, flat rocks to make a couple of walls in the base of this huge pile but for what purpose? To your right you'll see yet another low wall constructed of the same type of flat rocks. Finally you reach a large flat open area at the base of this cliff and are amazed to see a huge opening in the base of the cliff. You have reached the "Ice Cave"!

People are too young to remember that this is not a cave at all; it was blasted out of the iron-bearing rock that defines it. This was once known as the Fulmer Mine, also called the Marble Mountain Mine. Opened in 1860­­re-explored in 1880 and again in 1886­­ it has been claimed that over 1000 tons of usable ore was mined, but there is no known record that any of it was actually shipped. Examine the rock walls inside and outside of the opening and you will see much evidence of the tons of rusty iron ore that was taken from here. In fact, the huge pile of rock that you passed on the way up here was blasted out of this space. The cliff in which the opening is located was formed by miners blasting away the side of the knoll, before finally tunneling in to make the "cave".

Inside, the "Ice Cave" is about 40' wide, 30' deep front to back, and ranges from about 3 to 7 feet high. The small "room" to the left of the main room is a bit taller. Probably the same amount of rock was blasted or removed from the knoll in front as was blasted from the mine itself. This formed the flat face of rock at the front of the mine before the miners finally began excavating the rock within, leaving the room as it is today.

If you visit this mine during some cold winter day, you will see the floor covered with stalagmites made of ice, resembling so many old-fashioned milk bottles standing in groups. The icy stalagmites form when the air and floor are cold enough to quickly freeze the water that drips from the roof above. Over a period of time, the frozen water droplets build up into ice stalagmites, creating a beautiful, almost surrealistic scene within the mine.

The side trail that led here continues around to the north, eventually looping back until you are on the top of the mountain directly above the mine. If you continue to the highest point just beyond the surface workings, you will be surprised by the sudden appearance of a huge water tank and be pleased with a great view of parts of Lopatcong and Phillipsburg. Be very careful here because the drop-off is dramatic, at least 70 feet straight down!!

Retrace your steps back down the trail, past the mine entrance, and back to the intersection with the Highlands Trail. Turning left returns you to the parking area, while turning right takes you along the rest of the old road before it narrows down to a mere footpath a short distance away. About 200 yards from the intersection is yet another large exploratory pit and piled stone. Across the trail from this trench is an overlook, marked by a large stone firepit, high above the river road below. From here you can look across the Delaware River and see St. Anthony's Nose, an outcropping and overlook on Mt. Weygadt.

Continuing on the Highlands Trail, a short distance beyond the overlook the lane ends and the trail narrows down to the width of a rabbit path. If you continue exploring beyond here you might just find the future route of the Highlands Trail. If you turn around and return to the parking lot you will have hiked more or less 2 miles and will have climbed about 375 feet in elevation, not bad if you only had an hour or two to spend.


Lake Marguerite Wildlife Refuge

The 22-acre Lake Marguerite Wildlife Refuge offers a flat, well maintained trail network through a diverse mix of ecosystems. The main trail, marked with a red diamond, skirts a large open grassy field surrounded by hardwood trees. A short stretch of partially shaded woods turns a corner and opens to a small pond, complete with bench, picnic table and stone fireplace.

Although this park is well maintained, it is not overly groomed and retains its inherent natural feel. The flat, easy trails are perfect for a family to explore, and the red diamond trail twists and turns through a deeply shaded wooded marsh where half a dozen bridges take you over a beautiful trickling stream beyond the pondside picnic area. Naturalists will love the lush, varied growth and wildlife, which also offer artists and photographers ample subject matter.

The park entrance is on Jonestown Road (CR 625), about 400 feet northeast of the intersection of that road and Brass Castle Road (CR 623). A short gravel driveway leads into a small parking area.


Roaring Rock Park

Roaring Rock Park, another of Washington Township's beautiful natural parks, reflects a local story about the loud roar that can be heard as the water of Brass Castle Creek rushes past certain boulders during periods of very high water. The land for this park, which covers a few hundred acres, is set aside for passive use, including hiking and picnicking. Fishing is allowed in the creek, which is stocked with trout.

The network of trails offers varying amounts of difficulty and challenge for hikers, ranging from very easy to moderately difficult. An easy "family trail" heads down from the parking area toward the creek and a picnic area. Three harder trails loop around the park in a variety of ways, each ascending the knoll to the south, providing an elevation gain of about 225 feet upon reaching the summit. These trails can be combined to achieve hikes up to about 2 miles in length.

The trails vary in width, visibility, and surface ranging from soft wood chips to hard rocky projections. Good hiking boots are recommended for hikers using these longer trails to the summit.

The first part of each trail is near the creek as it flows rapidly down a rocky course. Several bridges are used for trail crossings. Further along, each trail leads away from the creek through moderately thick woodland populated mainly by hardwoods. A mountaintop meadow lies west of the summit.

Access to the park is on Brass Castle-Harmony Road (CR 647), about 0.6 miles from its intersection with Brass Castle Road (CR 623). Look for a sign designating the area on the south side of the road. A short drive down a gravel road ends in the parking area.

This story was first published: Summer, 2006

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