The village sits on the western tip of the Eiderstedt peninsula, roughly 45 kilometres southwest of Husum, where the peninsula shoulders out into the German Bight. Its beach runs about twelve kilometres and, at low water, opens out as much as two kilometres wide - not a strip but a plain, built from two offshore sandbanks, the Hitzsand and the Hochsichtsand, that drifted in and welded themselves to the mainland. Behind the sand lie dunes, salt meadows and planted woodland that has no business growing on this coast at all. The salt meadows are unusual even by Wadden Sea standards, pocked with ponds and puddles and flooded by seawater only occasionally rather than twice a day, so that grass frogs, moor frogs, common toads and even natterjack toads breed successfully within sight of the North Sea. Part of the municipality lies inside the Schleswig-Holstein Wadden Sea National Park, and the tide moves through up to three metres of range - which is why anyone walking out onto the flats is expected to consult the tidal calendar first and to mean it.

The buildings that put this place on postcards stand out on the sand itself, raised on timber legs above the reach of the tide. The first of them went up in 1911 and gave itself a name with a wink: the Giftbude. In the local dialect es dort wat gift means, roughly, there's something to be had there - and what was to be had, if you knew to ask, was cognac. More followed, and today the stilt houses strung along the flats are the signature of the resort, holding restaurants, lifeguard stations and shelter for the roughly 1,400 wicker beach chairs distributed across five bathing areas. From the water's edge at low tide they appear to be standing in the middle of nothing at all. Six hours later the reason for the legs is obvious.

St. Peter-Ording is a stitched-together thing, several once-separate settlements sharing one hyphenated name. The village of St. Peter appears in the record in 1373, though it had been called Ulstrup before - the change of name followed the loss of a great deal of land to the sea, and there is evidence of Viking-era settlement in the area before that. Suederhoeft and Boehl gave up independence after the flood of 1553. The parishes of St. Peter and Ording joined in 1867, but the two communities did not formally merge until 1967, and the municipality only moved into the district of Nordfriesland in 1970, having previously belonged to Eiderstedt. Politics arrived from outside too: this was Danish territory until 1864, with the border on the Eider a few kilometres south, and it was the Danish crown that finally ordered the wandering dunes planted and pinned down. St. Peter became Prussian in 1867.

Before the hotels, one reliable trade the coast did offer was picking up what the sea brought in. The beachcombers here were called Hitzloeper, and they worked the strand for flotsam - timber, cargo, whatever a wreck or a careless ship had given up. Valuable finds had a way of disappearing before an official could see them, since declared salvage carried duty and undeclared salvage did not. It was not a living so much as a supplement, gathered in the gaps between a failed harbour, a hard farm and a church that kept vanishing under a dune.

The resort grew in careful increments. The first hotel opened in 1877, a sanatorium followed in 1913, and a pier went up on Ording beach in 1926. In 1932 the railway from Husum was extended past Garding to the village, and much later the Eidersperrwerk barrage across the Eider gave the peninsula a proper road connection. The decisive discovery came in 1953: a strong iodine brine spring, which in 1958 earned state recognition as a North Sea healing and sulphur spa, a rare pairing for a German seaside resort. The pitch was the air as much as the water, salt-laden and low in allergens, prescribed as thalassotherapy. It worked. With fewer than four thousand permanent residents, St. Peter-Ording drew 1.361 million overnight stays in 2017, the second-highest total of any North Sea resort in Schleswig-Holstein and third statewide. That enormous flat beach found a second career too: hard, level and windy, it is one of Europe's great grounds for kitesurfing, windsurfing and strandsegeln, the wheeled cousin of sailing, and it hosted a Kitesurf World Cup every year from 2006 to 2015 in front of crowds well over a hundred thousand.