April 4, 1973: The Original World Trade Center

The original World Trade Center, with a previous

"tallest building in the world," the Woolworth Building,

between, and dwarfed by, the Twin Towers.

April 4, 1973, 50 years ago: The original World Trade Center opens, on the Hudson River in Lower Manhattan. The original complex consists of "Twin Towers": A North Tower, with the address of 1 World Trade Center, 1,368 feet high; and a South Tower, 2 World Trade Center, 1,362 feet high.

It replaces the Empire State Building, 1,250 feet, as the tallest building in the world. It didn't last long as such: A month later, the Sears Tower in Chicago was topped off, at 1,454 feet high. The Empire State Building had 102 floors, while the Twin Towers and the Sears Tower each had 110.

The site was bordered by Vesey Street on the north, Church Street on the east, Liberty Street on the south, and West Street and the West Side Highway on the west. At the time, that was the western edge of Manhattan Island. In the years to come, landfill would extend the Island by 3 blocks to the west, allowing for the building of Battery Park City in 1981 and the World Financial Center in 1985.

From 1921 to 1966, the site was known as Radio Row, full of electronics stores and warehouses. It would be replaced with an idea that had been batted around since 1943, of a "world trade center," uniting the world through commerce.

By the 1950s, the East Side, near the South Street Seaport, was the intended choice. But in 1962, an agreement was reached between Governor Nelson Rockefeller of New York, Governor Richard J. Hughes of New Jersey, and Austin J. Tobin, director of the Port Authority of New York and New Jersey, to build it on the West Side, near the Hudson Terminal of the Hudson & Manhattan Railroad, which, that year, was renamed the Port Authority Trans-Hudson, or PATH, system.

Minoru Yamasaki designed the towers. They were not as interesting as the Art Deco skyscrapers that had been built in New York in the 1920s and '30s, such as the Empire State and Chrysler Buildings. Indeed, while they were a magnificent engineering achievement, they were not artistic marvels. I've often said, "No one loved the Twin Towers until they were gone."

By the end of 1966, Radio Row was completely demolished. Construction began on August 3, 1968. Among the men involved in the construction was an elevator installer for the Otis Elevator Company, who had once been an All-Star for the Brooklyn Dodgers: Carl Furillo. The North Tower was topped out on December 23, 1970; the South Tower, on July 19, 1971. On April 4, 1973, they were formally opened.

The complex was expanded. In 1972, the Deutsche Bank Building opened, 517 feet and 39 stories high, and would receive the address of 5 World Trade Center. 6 World Trade Center, only 92 feet and 8 stories high, opened in 1974, and hosted various federal government offices, including the U.S. Department of Commerce and the U.S. Customs Service.

In 1977, 4 World Trade Center opened, at 118 feet and 9 stories. It hosted the New York Board of Trade and the Commodities Exchange Center. The climactic scene of the 1983 comedy film Trading Places was filmed there.

On July 1, 1981, 3 World Trade Center opened. It was a 242-foot, 22-story hotel, known first as the Vista Hotel, and later as the Marriott World Trade Center. The ground around the Center was named Austin J. Tobin Plaza for its founder, and lunchtime concerts were often held there, ranging from classical to rock. The complex was completed in 1987, with 7 World Trade Center, 610 feet and 47 floors, occupied mostly by the investment firm of Smith Barney.

In 1979, a TV antenna was added to the North Tower, raising the complex's height 1,730 feet. This would be 1 foot taller than the antenna atop the Sears Tower. However, by this point, the CN Tower in Toronto had reached 1,815 feet, becoming not "the world's tallest building," because its highest occupiable level wasn't as high as the ones in New York and Chicago, but "the world's tallest freestanding structure."

The Twin Towers messed with the perspective: They were half again as tall as the otherwise tallest buildings in Lower Manhattan. Pictures of Lower Manhattan at the time showed the Towers and a lot of sky. But they were an unmistakable symbol of New York City.

This made them a tempting target for terrorists. In 1993, an attempt was made to bomb them. It badly damaged a parking garage, and killed 6 people. In 2001, the terrorists tried again. They were successful.

It took until 2014 for the new World Trade Center, led by a single skyscraper, to open to the public. Its spire gives it the height of 1,776 feet, matching the year of the Declaration of Independence. Its Observatory opened on May 29, 2015. Officially, it has 94 stories, compared with its predecessor's 110. But the top floor is labeled the 104th, and it is 1,268 feet above the ground. The roof is 1,368 feet, matched the height of the previous One World Trade Center.