Penn Central declares Section 77 bankruptcy in what was the largest U.S. corporate bankruptcy to date.

The Penn Central Transportation Company, commonly abbreviated to Penn Central, was an American class I railroad that operated from 1968 to 1976. Penn Central combined three traditional corporate rivals, the Pennsylvania, New York Central and the New York, New Haven and Hartford railroad, each of which were united by large-scale service into the New York metropolitan area and to a lesser extent New England and Chicago. The new company failed barely two years after formation, the largest bankruptcy in U.S. history at the time. Penn Central's railroad assets were nationalized into Conrail along with those of other bankrupt northeastern railroads; its real estate and insurance holdings successfully reorganized into American Premier Underwriters.

American railroad company Penn Central Transportation Company declared bankruptcy on June 21, 1970, two and a half years after its formation by the merger of the New York Central Railroad and the Pennsylvania Railroad. At the time, this was the largest bankruptcy in American history. Penn Central was responsible for a third of the nation's passenger trains and much of the freight rail in the Northeastern United States, and its failure would have devastating impacts on the Northeast's economy.

Bankruptcy is a legal process through which people or other entities who cannot repay debts to creditors may seek relief from some or all of their debts. In most jurisdictions, bankruptcy is imposed by a court order, often initiated by the debtor.

June 21 is the 172nd day of the year in the Gregorian calendar; 193 days remain until the end of the year.