Gary Hartloff lives just a couple minutes down the road from the small cemetery where his ancestors are buried. The tiny portion of land, which Hartloff regularly mows and manicures, is dotted with gravestones dating back to the early 1800s, protected by a high fence, two padlocks and some shrubbery.

Mere yards away sits New Era Field — a huge, 200-acre complex that’s home to the US National Football League’s Buffalo Bills team, cramming in nearly 70,000 attendees at each home game.

The tiny, nearby graveyard is the Sheldon Family Cemetery, and it’s nestled smack in the middle of this American football stadium’s car park in Orchard Park, New York.

It once rested on private farmland. Today, its location is decidedly less serene grounds for eternal rest.

There, thousands of NFL fans party with copious amounts of alcohol before home games in the car park and then make their way to the stadium gates. The rowdy fans are largely unaware that the quaint, fenced-off plot of land standing between their parked vehicles and the stadium is a cemetery containing more than 20 graves of a New York state family. The exact number is unknown due to sparse records and unmarked graves.

It’s not that the cemetery is secret or concealed. It’s simply hidden in plain sight, placed immediately between the VIP parking lot and one of the stadium’s entrances, obstructed by some trees. Visitors might also pay more attention to the portable toilets that sometimes line the semi-hidden graveyard's perimeter.

Depending on the angle, the graveyard can be clearly seen. But most people don’t know about it — or choose to ignore it. Descendants of the Sheldon family prefer to keep it that way.

“We came over here one time, probably 20 years ago, and all the stones were all tipped over and letters chipped off it — vandalism,” Gary Sheldon said while raking freshly cut blades of grass from his ancestors’ tombstones.

This prompted the Bills to build around the cemetery and plant foliage as a buffer between tailgaters and the somber graveyard. “Ever since, [the Bills] tightened security over here nobody comes back. Because you could drive back here at any time. There was no security. But I appreciate that there is security now.”

It's hardly the first time that infrastructure or construction projects have brushed up against the resting places for the dead: They can sometimes be found in car parks of malls, and the careful excavation of mass burial sites has caused delays to rail-line construction in the UK.

A less common spot, however? In the shadows of a stadium belonging to a team that's part of the most profitable, popular sporting league in the United States.

A resting place surrounded by Portaloos

So how did more than 20 people end up buried in a highly trafficked car park? The answer dates back nearly two centuries, long before the Buffalo Bills team was established in 1960.

It started in 1832 when Joseph Sheldon, a surveyor for the Holland Land Company, asked his neighbour Solomon Curtis if he might have permission to bury his infant son John, who died just weeks after birth, in the clearing of an apple orchard a short walk from a local creek.

Curtis permitted the burial, eventually deeding the small parcel of land to Joseph Sheldon with one stipulation, according to a 1986 article in the Orchard Park Bee, a local newspaper: Joseph must reserve a plot of land for Curtis to be buried when the time came. (It’s unclear, however, if Curtis was ever actually interred in the land as he had requested.)

But through the years, the cemetery grew: Joseph Sheldon died, was buried beside his infant son John, and was followed by his wife Tryphena, their children, plus members of the extended family, neighbours and descendants. The last cemetery plot was dug after 1920, shortly before the Curtis family sold the surrounding land to the DuPont Company, the American chemicals conglomerate.

The descendants of those buried in the sporting arena's car park still live in the area to this day.

Dean Hartloff, a direct descendant of Joseph and Tryphena, and Gary Hartloff’s distant cousin, explained that the cemetery went unnoticed for decades. Grass, dirt and brush obscured stones, inscriptions faded flat with time, and some stones disappeared altogether.

Ownership of the land around the cemetery changed hands a few times. It was eventually sold to Erie County to build the Bills stadium.

In the US, the NFL is a cultural phenomenon: in 2015, the top 12 television shows of the fall season were NFL games, according to a USA Today report. Last season, the NFL's revenues reached $13 billion (£10.4 billion).

According to family lore, Ralph Wilson, owner of the Bills at the time of the sale to Erie County, planned to position the football field’s 50-yard line right where the cemetery was located — until the Sheldon descendents got wind of the tentative plan to exhume the graves.

“When the county decided to put the football stadium out there, they had to get the approval of the living relatives of those in the cemetery,” Dean Hartloff said. “I had a couple hard-headed great-aunts” — one of whom was his aunt Hermine Hartloff, the mother of Gary Hartloff, the cemetery’s sole groundskeeper today — “who refused to sign off, who wouldn’t let them move the cemetery.”

“But Ralph Wilson didn’t wait, he just built around it,” Dean Hartloff said of the team’s previous owner.

The stadium design was flipped as to not disturb the graves. Unfortunately for the Bills, the stadium’s open end had to face east-west rather than north-south, allowing a sort of lopsided crosswind to enter the stadium that is often blamed for kickers’ and quarterbacks’ in-game blunders.

The curse of the Bills

It’s true: The physical presence of the cemetery has inadvertently hindered the Bills performance on the field.

But some believe that it’s greater, stranger forces than uncooperative winds that’s punished the team — which notoriously lost four consecutive Super Bowl championship games in the early 1990s.

According to a marker at the entrance of the Sheldon Family Cemetery, “an early Erie Indian village was also located on the site of the stadium.’’

In 2012, writer Aaron Lowinger researched the area where the stadium is located, and found that a community of Wenro Indians once occupied the land. Western New York, to be clear, was once populated by various Native American tribes. The 1797 Treaty of Big Tree was largely responsible for forcing many of the native tribes in and around Buffalo from their homes and into reservations, so it’s generally safe to assume that all of Buffalo and its surrounding suburbs once belonged to Native Americans.

In his research, Lowinger found a 1920 “atlas of aboriginal localities” that specifically identifies the land on which the stadium is built as an Indian burial ground. “A large cemetery was destroyed by contractors and many clay vessels were broken and thrown in excavation,” the atlas entry reads.

“They didn’t just pave over. They dug into it. If this were happening today, maybe there’d be more respect to whatever’s there,” Lowinger said. “[It was] just a postcolonial mess up there. The Native American village that’s historically and anthropologically significant — it was dug up.”

So not only was the stadium almost responsible for disturbing the Sheldon cemetery — but documentation indicates that stadium was built on a Native American graveyard.

“You don’t fool with sacred grounds,” Gary Hartloff said. “They didn’t ever explore whether there was Indian burial grounds there.”

Who owns the cemetery?

Many die-hard Bills fans don’t even know the graveyard exists, since it’s partly hidden in the very car park where they drink and party before each home game.

Not even current team owner Terry Pegula had heard of it — until a few weeks ago.

When approached outside the stadium (a football’s throw from the cemetery) before a Bills match against the New England Patriots on 30 October, Pegula said he was unaware the cemetery even existed.

“I didn’t even know that,” he said in response to a request for comment. “So I can’t help you.”

So, why has the cemetery endured so long? Why hasn’t it been bulldozed to make room for more parking spaces, or a hot dog stand?

It’s because the Bills don’t own the cemetery. Problem is, no one knows who actually does… not even the Hartloffs.

Before moving from western New York to the Baltimore area in 2000, Dean Hartloff made frequent visits to the cemetery to clean it up, just as his parents, aunts and uncles before him had done. But with Dean Hartloff now living hundreds of miles away, and with his parents, aunts and uncles deceased, his cousin Gary Hartloff is the sole Sheldon descendent to take responsibility for maintaining the family cemetery grounds.

The trouble for both Gary and Dean Hartloff is they’re not sure who will step up to tend to their ancestors’ graves.

Younger members of the family tree have expressed interest in pitching in, but none have kept their word, Gary Hartloff explained while cleaning grass cuttings from headstones in the cemetery.

“When I take a dirt bath it’ll probably all go away, you know what I mean?” he added, rake still in hand.

What’s more, Gary Hartloff says he doesn’t know who owns the cemetery. He assumed the town of Orchard Park owned it. Orchard Park doesn’t own it, though. And neither does Erie County, which owns the stadium and its parking lots.

“Erie County owns the entire facility. We leased the stadium structure to New York state, which then subleases it to the Bills. The parking lots are owned by the county and leased by the Bills,” says Erie County Executive Mark Poloncarz. But the Sheldon Family Cemetery is “the only parcel in that entire complex, of the hundreds of acres, that is not owned by Erie County.”

“It’s sort of a mystery who owns it,” Poloncarz admitted. But based on the records he does have, he knows for certain that the family has access to the cemetery in perpetuity, and he suspects a family member does have the deed in his or her possession.

Finding a cemetery in a seemingly unlikely place isn’t as uncommon as it may seem. In the US alone, there are multiple documented burial grounds in car parks and roadways, such as the Burr family cemetery in a Long Island Home Depot parking lot and the final resting place of Mary Ellis outside of a New Jersey cineplex. Then there are the undocumented burial grounds that are discovered during construction.

The reality is that cemeteries are everywhere, below our feet – and tyres. We just don’t know it.

The Bills have been pressured by NFL executives in recent years to move the stadium to a new location, which would leave the cemetery in limbo beside a vacant football field, surrounded by a vast expanse of parking spaces.

Poloncarz isn’t worried, though. The Bills are just entering the fourth season of a 10-year lease.

As for the supposed Bills curse, he’s not buying it.

“I feel confident for the near future that the Bills will be playing in Orchard Park with the Sheldon family watching over them for some time,” Poloncarz said. “In the long run we will win the Super Bowl, and I don’t think the stadium location will have much of an effect on it.”

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