Slovakia celebrates the second of two National Days, called Constitution Day on September 01, 2017. Constitution Day in Slovakia commemorates September, 1 in 1992, when the constitution of the furthermore independent states got passed in Bratislava. Slovakia proclaimed itself sovereign in July 1992.
Then in September the Constitution of the new Republic had been accepted in a referendum. So that became the day when Czechoslovakia split into two independent states: Slovakia and the Czech Republic. Since that year Constitution Day in Slovakia, also known as Constitution Day in the Slovakian Republic, is held annually.