The Athens Polytechnic uprising in 1973 was a massive demonstration of popular rejection of the Greek military junta of 1967–1974. The uprising began on November 14, 1973, escalated to an open anti-junta revolt and ended in bloodshed in the early morning of November 17 after a series of events starting with a tank crashing through the gates of the Polytechnic.
November 17 is currently observed as a holiday in Greece for all educational establishments; commemorative services are held and students attend school only for these, while some schools and all universities stay closed during the day. The central location for the commemoration is the campus of the Polytechneio. The campus is closed on the 15th (the day the students first occupied the campus on 1973). Students and politicians lay wreaths on a monument within the Polytechneio on which the names of Polytechneio students killed during the Greek Resistance in the 1940s are inscribed. The commemoration day ends traditionally with a demonstration that begins from the campus of the Polytechneio and ends at the United States embassy.
The student uprising is hailed by many as a valiant act of resistance against the military dictatorship, and therefore as a symbol of resistance to tyranny. Others believe that the uprising was used as a pretext by Brigadier Dimitrios Ioannidis to put an abrupt end to the process of ostensible liberalisation of the regime undertaken by Spiros Markezinis.
From Wikipedia’s page “Athens Polytechnic uprising.”