Sofia is the capital city of Bulgaria. Countries, not cities, join the European Union. Bulgaria joined in 2007.
No countries joined the EU in 2010. Before 2010, Romania and Bulgaria were the newest, joining in 2007.
Croatia in 2013 and Bulgaria and Romania, both in 2007.
Romania and Bulgaria are members of the European Union from 1 January 2007.
Bulgaria has not yet joined the Euro zone, it joined the EU in January 2007.
Monaco did not join the EU.
Since 1 January 2007 Bulgaria has been a full member of the EU.
Nato, EU
Eu, NATO
Yes, Bulgaria is on the continent of Europe and joined the EU on 1st January 2007.
It became an EU member on 1st January, 2007.
Croatia is the newest member, having joined on the 1st of July in 2013. Before that, Romania and Bulgaria were the last two countries to join the European Union and did so in 2007.