On July 7, 1999 the U.S. Embassy in Germany moved from Bonn to Berlin. A bit of history is in order
(link). The U.S. State Department's history is here
(link) .
Before the U.S. broke diplomatic relations with Germany in 1941, the embassy was located in Berlin. After the end of WW II Germany was split into East Germany, otherwise known as the Democratic Republic of Germany and West Germany, otherwise known as the Federal Republic of Germany. The U.S. initially didn't have diplomatic relations with either "Germany." We established relations with West Germany in May 1955 and East Germany in September 1974. When the countries reunited in 1990 we turned the East German embassy into a "branch." The German Embassy was in Bonn, where the West German embassy had been located. On July 7, 1999 we moved the embassy to a reunited Berlin.
One can argue that the move was deeply provocative to Russia. Russia had, just nine and one-half years earlier had effective control over East Germany. We were taking a stand on a regional controversy.
One could argue that we spent tons of money on the new embassy and received no tangible benefit. Some argue that we should get tangible benefits for embassy moves. I'd like to hear there's and other's views.