Three hundred fifty years ago, a British royal decree created New Jersey’s first “subdivision,” the provinces of East Jersey and West Jersey. But the Duke of York, who gave the land to two loyal friends, didn’t explain how to divide it.

That job fell to Surveyor-General George Keith, who was charged with plotting the exact boundary — or Province Line — running diagonally from the Atlantic Ocean to the Delaware River in a northwesterly direction.

Keith started in Little Egg Harbor and got as far as Three Bridges in Hunterdon County in 1687 when it became clear that he was off by a couple of degrees, giving too much land to East Jersey.

More surveys would be needed to divide the territory accurately, a process that took another 57 years.

But the original “Keith Line” remains as both an historic curiosity and actual boundary between several counties. Take a look at a map and you’ll see the line separating Burlington County (West Jersey) from Ocean and Monmouth (East Jersey).

To celebrate New Jersey’s 350th anniversary, Mount Holly resident Bill Bolger plans to “walk the line” later this year, following George Keith’s footsteps as closely as possible. Bill will walk approximately 150 miles over the course of three weeks.

“I’m excited. I think it’s going to be fascinating,” said Bill, who is taking time off from his job with the National Park Service to make the trek.

One aspect that excites Bill is that the route will cross nearly every type of New Jersey geography — from ocean beaches to pine forests to freshwater swamps to mountain ridges. “If you walked from Atlantic City to Philadelphia, you’d never leave the coastal plain,” he said.

As a bonus, the line goes through extensive amounts of preserved land. “It involves almost every aspect of the state’s conservation history — farmland preservation, state parks and forests, wildlife refuges, the Pinelands. It’s an amazing sequence of conservation stories,” said Bill.

The Keith Line also serves as an unofficial cultural boundary in the Garden State, separating the “North Jersey” folk who root for New York sports teams from “South Jersey” residents who cheer for Philadelphia.

Bill plans to test this cultural theory by asking people along the line whether their sports allegiance lies with New York or Philly.

Bill will begin his journey on the dunes at Holgate on Long Beach Island in late September and finish at Tocks Island (Warren County) in the Delaware River, averaging about seven miles a day.

In between, he’ll stop at historic sites, tourist attractions, parks, farms, museums and other landmarks. He intends to take photos and videos, chat with locals, and post his discoveries on a blog.

While the Keith Line is arrow straight, Bolger’s route won’t be … and can’t be. Some pieces of original “Province Line Road” exist, but in most places there’s no trail to follow. So Bill is cobbling together an indirect route along local roads and hiking trails that parallel and cross the line.

His route won’t deviate from the line by more than a mile, but the zigzagging adds 40 miles to what would otherwise be a 111-mile, as-the-crow-flies path.

Long treks are nothing new to Bill. On three occasions, he’s walked the full length of Manhattan Island, from the Bronx to the Battery. And he once walked 220 miles through Pennsylvania. As he walks, he’ll keep conservation forefathers like Henry David Thoreau and John Muir in mind. “They thought nothing of walking a couple of hundred miles,” he said.

Bill is still in the process of plotting his exact stops along the Keith Line and how he will document them in a blog. Stay tuned for more.

The South Branch Wildlife Management Area and adjoining Clover Hill Park — which is alongside the Keith Line — consist of 553 acres of rolling fields, mature woodlands and several creeks. While Clover Hill is owned by Hunterdon County, the state owns the WMA but in 2008 entered into an agreement for Hunterdon County to manage the whole property. Audubon is also involved.

Byers is executive director of New Jersey Conservation Foundation. Reach her at info@njconservation.org.

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