Vienna, Austria
none
i think it in turkey.
Rotterdam is in the Netherlands. It is a city, and does not border any countries.
The Danube River forms the border of some countries. They are Romania, Bulgaria, Hungary, Serbia, Slovakia, Austria and Germany.
None, Austria is landlocked.Except that in some places the border goes through a lake or is in the middle of a river. For example in the west the Austrian border with Germany and Switzerland runs through a lake called Bodensee.
None, Vienna is a city not a country.
The Danube runs through Germany, Austria, Hungary and Serbia. It borders Part of Serbia and Croatia, Hungary and Slovakia, and Romania and Bulgaria.
Russia mobilized against its border with Germany when it went to war with Germany's ally, Austria-Hungary. It was a preventative measure that the Germans took as a threat and made them declare war.
The Central European country of Austria is bordered by eight countries. The Czech Republic and Germany are to the north, Hungary and Slovakia are to the east, Slovenia and Italy are to the south, and Switzerland and Liechtenstein are to the west.
Russia mobilized against its border with Germany when it went to war with Germany's ally, Austria-Hungary. It was a preventative measure that the Germans took as a threat and made them declare war.
Hungary does not share a common border with Switzerland.