If you’d been a child in the late 1800s, the Atlantic City boardwalk would have been a place of pure wonder. Racing across the wooden boards, saltwater taffy in hand, you could weave between the legs of big-city visitors and the rolling chairs, pushed by dapper attendants, in which the wealthy rode past grand hotels. Opposite Applegate’s Pier was a carousel, mesmerizing crowds with its hypnotic revolutions and the siren song of its organ, piping out popular songs.

Though originally designed as a temporary solution to keep the sand out of seaside buildings, the boardwalk—a simple raised wooden walkway—is an American institution. It has supported the feet of revelers for 150 years—an iconic place to people-watch, buy a hot dog, check out a sideshow or ride a Ferris wheel.

New Jersey is the birthplace of the structure, offering entertainment by the sea all along the Jersey Shore. Atlantic City’s boardwalk is the oldest, longest and grandest, even giving its name to the most expensive property on the Monopoly board. Boardwalks sprung up in imitation of it across the US, each with their own local flavor: fairground rides in Coney Island, stuntmen in Santa Cruz, bodybuilders and fortune-tellers in Venice Beach.

City dwellers flock to boardwalks when the routine of urban life can no longer contain them. Over decades, the entertainment has changed, but the boardwalk’s chief draw is the same: the thousand moods of the ocean. Since beaches are often private property, boardwalks are an egalitarian space where anyone may enjoy the sea, but also a tool to keep man and nature separate, to parcel wildness into pretty views.

It’s not all just about the fun and games on top of the boardwalk, however: The space underneath has long fascinated artists. In the crooner classic “Under the Boardwalk,” the Drifters describe it as a place where lovers find some hard-sought privacy. And generations of photographers have documented that underworld of complex shadows, home to city detritus, encampments of homeless people and the occasional dead body.

The boardwalk’s glamour was already fading by the middle of the 20th century, and by the 1970s many boardwalks had gone into decline. The soft, splintering wood of their walkways was often replaced by concrete. (When it was not, joggers occasionally fell through the rotting boards into pits of trash.) Gradually the word “boardwalk” became a byword for sin and decay. In fact, seediness was nothing new: Coney Island was once known as “Sodom by the sea,” and the HBO show Boardwalk Empire details criminal machinations in the Prohibition era.

It makes sense that humans should flock to the threshold between civilization and nature: It’s the eternal allure of life on the edge. But the boardwalk’s permanence depends on the sea remaining a stable distance from the shore. Unfortunately, erosion is disfiguring shorelines and Atlantic City has one of the highest risks of flooding in the country. Major hurricanes in 1944, 1962 and 2012 destroyed boardwalks, which some cities elected not to rebuild. On the other hand, over the years, the boardwalk in Wildwood, New Jersey has been moved twice to bring it closer to the ocean. Like so much in America, the boardwalk is founded on a myth. It is built to help us stand unbowed beside the enormity and indifference of nature, to convince ourselves, however briefly, that it can be contained.