site.btaObservances: April 28

The world:

- World Day for Safety and Health at Work.

On this date in Bulgarian history:

1951: The Brushlyan Irrigation System, this country's first engineering irrigation system, goes into operation.

1963: Telephone factory opens in Belogradchik.

1963: An electric hoist factory opens in Gabrovo, the biggest manufacturer of electric rope hoists in Central and Eastern Europe.

1964: Diplomatic relations with Italy are upgraded to embassy level.

1971: Diplomatic relations are established with Ecuador at embassy level.

2006: Bulgaria and the United States sign a Defence Cooperation Agreement, which includes the range, order and conditions of the shared use of several military facilities on Bulgarian territory.