On April 3 Sofia marks 139 years since it was declared capital of Bulgaria. The Sofia Municipality organized a series of events to mark this day. Sofia was proclaimed capital, because it was situated in the middle of the country whose territories were arranged by the San Stefano Peace Treaty and because it had a very high economic potential. In nearly one century its population increased with over 1 million people. Today, over 1.3 million Bulgarians live in Sofia. The city produces nearly 40% of the country’s gross domestic product and proved its motto Ever Growing, Never Ageing.