Arline Snead doesn't like to disturb the tenants in the 19th-century farmhouse or the Canada geese nesting beside a small pier over a green pond that conceals Parr's Spring and the little secret it holds.
But she telephones the tenants and gently shoos the geese, then leads the way to the secluded spot amid tall trees and ancient lilacs off a busy highway south of Mount Airy.
The secret lies under a tiny trapdoor about 8 inches square that her family cut in the pier to allow visitors a peek at history.
Raise the door and wait, for as the surface of the pond clears, a boulder becomes visible underwater. Placed in the 1700s and carved with a "P," it rests against a concrete post that nearly breaks the surface. The post was erected in 1951 by the state, with the initials C, M, H and F on the sides facing Carroll, Montgomery, Howard and Frederick counties.
Under the 1 3/4-acre pond and the little trapdoor in the 20-foot pier, lies the only point in Maryland where four counties meet, according to the Maryland Geological Survey.
Through the centuries, Parr's Spring water has served soldiers, farmers and a tannery. It became a resort in the late 1800s and later a popular spot for church picnics and weddings.
Surveyors have been quite fond of it. The phrase, "Beginning at Parr's Spring " occurs throughout reference works at the Historical Society of Carroll County. The landmark was used repeatedly since before the American Revolution to configure and reconfigure Maryland's counties.
Parr's Spring has been in seven counties during the past 305 years, including Prince George's, Anne Arundel and Baltimore counties, according to Snead's family history, local historians, reference books and maps.
For the past 149 years, Parr's Spring has marked the spot where the four counties meet. That's how Arline Snead can entertain visitors in Howard, sleep in Frederick and take a bath in Montgomery, without leaving her suburban brick ranch house across the road.
The land her ancestors bought in 1837 is named, not surprisingly, Four County Farm.
Snead, 78, keeps the family history and represents the fifth generation of owners since Nimrod and Elizabeth Harrison bought the first 120 acres, then known as Hobbs' Level. Snead and two cousins inherited the land, and they tend it with their grown children and grandchildren, who share a determination not to yield to the development in the Interstate 70 corridor.
"It's very historical and we love it, and we want to keep it going," said Snead. "Parr's Spring was established well before my family bought it."
"Mount Airy is growing so much," Snead's daughter, Linda S. Field, 52, said of their hometown, two miles north and equidistant from Baltimore and Washington.
The first land record to refer to Parr's Springs dates from 1744, when John Parr laid out a 200-acre tract he called Parr's Range, said George J. Horvath, a historical map and graph maker, retired but working part time for the State Highway Administration.
During the Civil War, Parr's Spring was a stop for the Army of the Potomac's Brig. Gen. David M. Gregg's cavalry, on June 29, 1863, while en route to Gettysburg, Pa., according to a map at the historical society from "Just South of Gettysburg" by Frederic Shriver Klein.
By the late 1800s, it was a resort, according to the "History of Western Maryland," an 1882 work by J. Thomas Scharf. He wrote about Parr's Springs: "At this noted resort, the four counties of Frederick, Montgomery, Howard and Carroll converge."
"We've had several weddings at the four-county stone," and people went to the spring after church for picnic lunches during the 1950s, Snead said. One group, Snead recalled, included then-Gov. Theodore R. McKeldin.
In the 1950s, Parr's Spring became a pond, dug and filled by seven spring heads that form the headwaters of the South Branch of the Patapsco River. That's why two of the three monuments placed over the centuries lie under water.
The simple boulder was carved with a P, once painted white. While many assume the P stands for Parr, Horvath said it could represent Prince George's County, which dates to 1695. "Before Frederick County, everything was Prince George's County: It ran all the way up to Westminster, all the way west and on up to Route 30 and Pennsylvania, and into Calvert County." The number "14" is carved on the top, but geological surveyors are unsure of its meaning.
Twenty-five years after the state sank the post beside the boulder, a third monument was placed on land above the spring by the Damascus Chapter of the Daughters of the American Revolution. Similar to a headstone, this 1976 marker proclaims "Parr's Spring: Headwaters of the Patapsco River. Boundary Point of Four Counties."
The counties are listed in two columns: Under the date 1776 are Frederick, Montgomery, Baltimore and Anne Arundel. To the right, under the date 1851, the list has changed to Frederick, Montgomery, Carroll and Howard.
Snead's brick ranch house was one of four in a row built on the original Four County Farm, which has grown to about 230 acres of mostly agricultural-zoned land, with eight houses and a classic red barn. Most of the land is in Howard and has been placed in protective zoning, said Robert R. Paylor, 53, who made the little trapdoor and is the son of one of the three Snead cousins.
The family has had a taste of development and didn't like it, members said. One of the four houses was sold by an aunt after a speeding car hit the house -- then a gasoline station sprouted at Routes 27 and 144, Snead said. Her mother's "older generation" also sold a parcel to 84 Lumber Co.
"We're going to hold the land," Snead said. "It will not be sold, ever. We might be surrounded, but there won't be anything here." Some of the seventh generation, in their 20s and 30s, have settled in the area, while others attend reunions from as far as Colorado, where the third cousin, Doris Rust, lives in Fort Collins.
"We all are very close because we get together and have picnics on the farm for all the generations -- and that's important," Snead said. "Each generation is holding it for the next."
Horvath applauds the family for protecting the land while making its secret known.
"It tells the people what's out the window, when you're flying past on Interstate 70," he said. "You may see the old road and Mount Airy and all the development -- and you might not realize what's right on the other side."