National flag raised in front of Parliament
The flag was hoisted in the presence of President Katalin Novak and house speaker Laszlo Kover, as well as members of the government, diplomats and as representatives of the state and military.
Families and tourists were also present in the square, many wearing cockades and holding Hungarian flags.
Festive events are being held throughout the country and beyond.
Prime Minister Viktor Orbán will give a speech in the afternoon in Kiskoros, in southern Hungary, the birthplace of revolutionary poet Sandor Petofi.