The 4th & Vine Tower (formerly known as the Union Central Tower and Central Trust Bank Building) is a 151 m (495 ft) skyscraper in downtown Cincinnati, Ohio. It stands 31 stories tall, overlooking the Ohio River waterfront. It is easily one of the most recognizable buildings in the city's skyline, owing to the elaborate Hellenic architecture in the upper portion of the tower, which was modeled to resemble reconstructions of the Mausoleum at Halicarnassus. Few PNC Bank employees now work in the 4th & Vine Tower today, as most report to the newer PNC Center. PNC Bank has the signage rights to the building, but PNC Tower is not the official name. It is officially the 4th & Vine Tower.

PNC acquired Central Trust in 1988. However, the signage on the building remained "Central Trust" until February, 1993. On September 16, 1992, PNC Bank announced it would scrap the names of its various banks in favor of the PNC Bank name. The lights on the old sign, which had been a fixture of the Cincinnati skyline since 1964, were turned off for the last time at 6:00AM on Monday, February 8, 1993. when workers began removing the "Central Trust" signage from the building and replacing it with a similarly-styled red-neon-lettered sign. The work on replacing the sign was completed in late-May of 1993 and three sides of the building were lighted with the new lettering. A nesting peregrine falcon had prevented the lighting of the sign on the east façade. This final sign was illuminated on July 26, 1993.

The site of the tower was previously occupied by the U.S. Post Office and Customs House and also at a later time by the Chamber of Commerce Building.

The 4th & Vine Tower was originally built as the headquarters for The Union Central Life Insurance Company, which moved out in 1964. At least four people died during the construction. When construction of the Cass Gilbert-designed building was completed in 1913, the Union Central Tower was the fifth-tallest building in the world and the 2nd tallest building (tallest office building) outside of New York City. The building opened May 1, with final construction costs of approximately $3 million. It remained the tallest building in Cincinnati until 1930, when construction on the Carew Tower was completed.

The building, along with the nearby skyscraper, the Carew Tower, was featured in the opening and closing of the daytime drama The Edge of Night from 1967 to 1980. Cincinnati had stood in as the show's locale, Monticello; the company that produced The Edge of Night , soap and consumer products maker Procter & Gamble, is based in Cincinnati. It was also featured in the opening and closing credits of the TV sitcom WKRP in Cincinnati, although the show was produced in Hollywood.

In March 2021, the structure was announced to be the new home of 250 apartments, office spaces, and a 'city within a city' concept by City Club Apartments. Construction is underway.

• List of tallest buildings in Cincinnati