It can be easy to forget that dense, frenetic Manhattan is in fact an island. But on 4 May, the 28th annual Great Saunter – a 32-mile urban hike – offers sure-footed explorers a chance to get in touch with the waterfront and gain a new perspective on the city along the way.

The roughly 12-hour walk, which passes through 20 parks and promenades and more than a dozen neighbourhoods, is organized by Shorewalkers, a nonprofit focused on promoting and preserving New York City’s shores. Distinct skyline vantage points, views of the New Jersey Palisades and vestiges of Manhattan’s past – including a 133-year-old lighthouse; a one-time roadside overlook built with Neoclassical flair; and the city’s oldest standing bridge – are just some of the sights that dot the trail.

“When you get out of lower Manhattan you find amazing things,” said event coordinator Sid King.

The route follows the Manhattan Waterfront Greenway from the southern tip of the island up the Hudson River to Inwood Hill Park; from there it’s across to the Harlem River before heading south through Harlem via Jackie Robinson Park. The Great Saunter’s path then takes advantage of a waterside esplanade between 145th and 135th Streets along the Harlem River, before rejoining the Greenway and winding down the east side. A post-trek celebration follows at Fraunces Tavern, a watering hole in the Financial District that dates back to the American Revolution.

More than 800 people from around the world are expected to take part in the rain-or-shine event. “Every age group and demographic is represented,” King said, noting the youngest previous Great Saunter participant was three months old (and in a stroller) and the oldest was 89 (he walked all 32 miles).

Training to build up for the long distance is recommended, but walking only some of the Saunter is perfectly fine – subway and bus stops are indicated on the route maps. “There are no judgments or disqualifications,” King said.

The Great Saunter starts at 7:30 am from Pearl and Broad Streets. On-site registration begins at 7 am, while late registration begins at 9 am at West 42nd Street and the Hudson River. To save time, you can also preregister online. The entry fee is $20 for individuals or $25 for two family members. Walkers are encouraged to bring an extra pair of dry socks, water, a light snack and cash.

Amy Brader is the New York City Localite for BBC Travel