site.btaObservances: March 31

The world:

Malta: Freedom Day (withdrawal of last British troops from Malta in 1979).

On this date in Bulgarian history:

1893: Bulgaria's first philatelic society is established in Plovdiv.

1901: Two quakes (measuring 7.2 and 7.1 on Richter Scale) strike Cape Kaliakra and Shabla (Northeastern Bulgaria). 

1981: National Palace of Culture in Sofia is inaugurated.

2000: Radio Bulgaria's web page launches a real audio news service in German.

2005: National Assembly ratifies Protocol on the Accession of the European Community to the Eurocontrol International Convention Relating to Co-operation for the Safety of Air Navigation of 13 December 1960, as variously amended and as consolidated.

2008: Bulgarian National Bank starts posting exchange rate statistics on its website.