The July 4 festivities celebrating America’s 250th birthday kicked off with a spectacular nautical display featuring the largest flotilla of tall ships from around the world, transforming New York City’s waterfront into a floating tribute to the nation’s milestone anniversary.

An estimated 6 million spectators lined the 15-mile waterfronts of New York and New Jersey on July 4, cheering on an armada of more than 40 historic tall ships and 30 U.S. Navy and international military vessels. The parade began at 9:30 a.m., sailing from the Verrazzano-Narrows Bridge, past the Statue of Liberty, up the Hudson River and on to the George Washington Bridge.

About 20,000 sailors — 10 times the number who participate in Fleet Week — joined the spectacle, which opened with a “wedge,” a triangular escort flotilla led by a pilot boat and flanked by security boats from the New York and New Jersey State Police.

Two FDNY vessels, the Fire Fighter II and the Three Forty Three, named in honor of the 343 FDNY firefighters killed on Sept. 11, 2001, greeted the ships with water salutes — some in red, white and blue — before leading them up the Hudson River, which Gen. George Washington had called the “key to America” while battling the British Navy during the Revolutionary War.

The USCGC Eagle, also known as “America’s Tall Ship,” led the parade and carried a special document for the voyage: one of the earliest original copies of the Declaration of Independence.

FDNY Fire Fighter II and the Three Forty Three greeted the vessels with water salutes.Photo by Gabriele Holtermann FDNY Fire Fighter II and the Three Forty Three greeted the vessels with water salutes.Photo by Gabriele Holtermann The USCGC Eagle carried a special document for the voyage: one of the earliest original copies of the Declaration of Independence.Photo by Gabriele Holtermann

Twenty-two nations, including Chile, Germany, Italy, France and Argentina, participated in the Sail4th 250 International Parade of Sail. Many of the ships sailed for weeks across oceans to honor America’s birthday.

Some of the vessels were more than 100 years old, including the Oosterschelde, a three-masted topsail schooner built in 1918 and representing the Netherlands. The country’s largest sailing ship was among the first tall ships to make its way up the waterway. The Netherlands was the first nation to officially salute the flag of the new United States on Nov. 16, 1776, marking a key step in securing U.S. sovereignty during the American Revolution.

The Oosterschelde from the Netherlands was among the first tall ships to make its way up the waterway.Photo by Gabriele Holtermann The NYPD provided security for the largest maritime celebration in U.S. history.Photo by Gabriele Holtermann FDNY Fire Fighter II and the Three Forty Three greeted the vessels with water salutes.Photo by Gabriele Holtermann

At about 10 a.m., the International Aerial Review soared over what organizers described as the largest maritime celebration in U.S. history. A massive formation of more than 175 military and heritage aircraft from the U.S. and allied air forces flew over the Hudson River.

The flyover was spearheaded by the U.S. Navy Blue Angels in their signature F/A-18 Super Hornets. The French Air and Space Force’s Patrouille de France flew over the harbor in Dassault-Dornier Alpha Jets, leaving trails of red, white and blue smoke.

A massive formation of more than 175 military and heritage aircraft from the U.S. and allied air forces flew over the Hudson River in honor of America’s 250th birthday.Photo by Gabriele Holtermann A massive formation of more than 175 military and heritage aircraft from the U.S. and allied air forces flew over the Hudson River in honor of America’s 250th birthday.Photo by Gabriele Holtermann A massive formation of more than 175 military and heritage aircraft from the U.S. and allied air forces flew over the Hudson River in honor of America’s 250th birthday.Photo by Gabriele Holtermann

The Sail4th 250 tall ships will be docked at four public tour locations from July 5 through July 8, including Brooklyn Bridge Park in Brooklyn, the South Street Seaport in Manhattan and Stapleton Park in Staten Island. Reservations are strongly recommended because of high demand. Tours at Pier 86 must be reserved through the Intrepid Museum.