There’s a New Beach in Manhattan. Just Don’t Try to Swim There.

Swimming is not allowed at Manhattan’s newest beach.

And yet. The water is oddly tantalizing. Yes, it’s the notoriously murky Hudson River, with Con Ed effluvia in it. But there’s no barrier between you and the waves, so I stood on the sloped concrete landing and allowed cool splashes of water to swirl over my feet.

The newly opened Gansevoort Peninsula Sand Bluff is in Hudson River Park in the Meatpacking District, where West Street meets Gansevoort Street, across from the Whitney Museum. The park purports to feature “the first public beachfront in Manhattan.”

One imagines that at some point, surely before and possibly after the Dutch started forming New Amsterdam in 1624, the island probably had public beaches.

There still are a couple of small, semi-secret, perhaps-not-entirely-technically-open-to-the-public beaches in Manhattan, including the pretty shoreline in Fort Washington Park, with its dramatic view of the George Washington Bridge, and the stretch of sand known as Tiny Beach up at Spuyten Duyvil Creek. But I digress.

At Manhattan’s new and official beach, the wide concrete pier contains a large sports field, boardwalks, promenades, a lawn, a picnic area, an ecological salt marsh and a strip of sand — brought in from a quarry near Cape May, N.J. — near a water access point meant for kayaks or canoes.

An inherent tension results when you open a beach where swimming is not allowed. On a recent Wednesday afternoon, a handful of people tested the waters, literally and figuratively.

Kateryna Shevchenko, 41, had come prepared, wearing a strappy bright red bathing suit. “The beach is something where people swim,” she said.

Ms. Shevchenko, who lives in Hell’s Kitchen and rode the bus to the beach, called the park “super cute.”

Still, she was a little disappointed.

“I don’t know why we cannot swim here,” she said, as she stood barefoot on the concrete landing, letting the river waters churn around her ankles. She kept glancing at a uniformed Parks Enforcement Patrol employee.

He, in turn, was watching her, and anyone else getting too close to the water. (Later, another woman argued loudly with two park employees after she was asked not to stand on a ledge.)

Signs near the water warn of dangerous currents and slippery rocks — not to mention occasional sewer discharge.

Nevertheless, Ms. Shevchenko was determined to wade farther in. “When this sheriff goes,” she said, with an eye on the guard, “maybe I will try.”

David Rosen, 77, had also walked into the water, “about halfway up my calf,” he said.

Mr. Rosen, who had arrived on the beach from the Upper West Side via the C train, was born in the South Bronx and had visited Orchard Beach and Jones Beach as a kid. How did the new beach compare?

“It’s 70 percent the same,” he said, as he lay, bare-chested, on the sand. “I’d like to go swimming.”

Still, Mr. Rosen gave the beach a passing grade. “Seventy percent is a big percentage,” he said. “One hundred percent would be better, but then, it took me 10 minutes to get here on the subway. Coney Island would take me an hour and a half.”

Melissa McIntyre and Ken Lin, who were sunbathing nearby, also mentioned the proximity, calling Rockaway Beach and Brighton Beach “a schlep.”

The new beach is just a 15-minute walk from their apartment in Chelsea.

Ms. McIntyre, 42, said she had lived in the East Village for 16 years and felt that the city had “neglected” the waterfront on that side of town.

“They don’t service that community,” she said. “They pick and choose.” She looked around. “Ninety percent of people here are white,” she said, and questioned whether the park existed because the city was “pandering” to wealthy neighborhoods. Still, she said it was her second afternoon at the beach — and that she would come back. “I can get used to this,” she grinned.

Mr. Lin, 49, agreed. “When they said that they were creating a beach in Manhattan, the vision in my mind was a lot different,” he said. “This is sort of like a large sandbox.” Still, he laughed, “I’ll take what I can get.”

Many had the same idea. It was 3 p.m. on a weekday and the park was full; all the bright blue Adirondack chairs were taken. Sunbathers in skimpy swimwear reclined on towels. A woman in a bikini typed on a laptop. Toddlers played quietly. People smiled as they took selfies, or photos of the view.

When a chair became available, I sat, removing my sandals. My toes sank into the soft, powdery sand. It was a brightly sunny 82 degrees. One World Trade Center and the Statue of Liberty shimmered in the distance. A sailboat drifted by. A gull flew overhead. The breeze was lovely.

I closed my eyes and focused on the gentle splashing sounds of the river, lulled into a state of calm.

Just then, a loud, long, awful bleat: “Meeeeaaaaaaaaaaahhhhhhh.”

A car horn. Just to remind you that you’re sitting in a sand pit next to the West Side Highway.