April 20th (1453) was a Wednesday. It's the 109th day of the year (110th in leap years) in the Gregorian calendar. There are 256 days left to the end of the year.
Historical Events for 20th April, 1453
» The last naval battle in Byzantine Empire or Byzantine history occurs, as three Genoese galleys escorting a Byzantine transport fight their way through the huge Ottoman blockade fleet and into the Golden Horn.