At first glance, it seems to be on an incline. Running my eye over it, sparsely grassed and gentle of curve, it strikes me as the sort of slope on which –given a coating of snow – children might spend a happy few hours on sledges.
The heat of the morning is the first clue that this is not Dickensian Kent on a frosted December day. The second indicator stands tall atop this 90ft hillock – a granite monument. Around its base, sculpted words give the game away entirely. "In commemoration of the conquest of the air by the brothers Wilbur and Orville Wright," reads the inscription. "Conceived by genius, achieved by dauntless resolution and unconquerable faith."
As places that changed the world go, the Wright Brothers National Memorial is understated. A quiet, undulating field, it sits in the small town of Kill Devil Hills, halfway down the Outer Banks – the 200-mile chain of interlinked sandbars and islets that shapes the shoreline of Virginia and (in this case) North Carolina.
Pull up a satellite image of this narrow landmass, and you'll be amazed that water has not yet engulfed it – barely a mile wide in parts, hemmed on one side by the open mouths of Currituck and Albemarle Sounds, on the other by the fury of the Atlantic.
And yet, it was precisely its exposed setting that made the North Carolina coast the ideal venue for the Wright Brothers' aviation experiments – home to high winds, but also the sort of soft, slanted terrain that assists take-offs and cushions crash-landings. The brothers first came here in 1900, travelling south from their native home of Ohio, and conducting tests with rudimentary gliders. But by 1903 they had advanced to the Wright Flyer, an aircraft made of very light but durable spruce, and fitted with an aluminium engine.
On 17 December, they completed four short forays (two per brother), the longest lasting for just 59 seconds and 800ft, that are now recognised as the first controlled powered airplane flights .
Their revolutionary trail is still visible. A boulder marks the exact location of that initial glorious uplift (with Orville at the controls) that slipped Earth's clutches and floated, however unsteadily, above terra firma.
Ebbing away from it, across the grass, the "Flight Line" maps those first four successes – further boulders at each touch-down point – that punched a hole in the fabric of the present, and dragged mankind into the future. It takes me four minutes to walk the path, but I can almost feel the centuries shifting as I do so.
Adjacent, a cluster of buildings supplies some context. Twin wooden structures – replicas of the brothers' living quarters, and what was the first hangar – are as basic as they would have appeared 109 years ago.
The Visitor Center deals in echoes, playing host to a reproduction of the wind tunnel used in the siblings' calculations, a life-sized model of the Wright Flyer (the real thing is preserved by the Smithsonian Institution at the National Air and Space Museum in Washington DC), and the doughty plane's actual engine block.
On the walls, grainy photographs – the Flyer tottering nervously into the blue; the two men well-groomed and proud, Orville fulsome of moustache – fatten out the story.
But the most pertinent reminder of what happened here lies outside. As I retreat into the blustery conditions beyond the museum, a tiny biplane spears up into the sky from the First Flight Airstrip that runs behind the complex.
As it turns towards the ocean, it dips a wing, as if saluting the Memorial – and the visionary men who altered all our tomorrows.
Wright Brothers National Memorial, 1401 National Park Drive, Kill Devil Hills, North Carolina (001 252 473 2111; nps.gov/wrbr). Daily, 9am-5pm; $4 (£2.50), under 16s free.