In 1954, in a gesture of friendship to mark the 300th anniversary of Ukrainian union with Russia, Soviet Premier Nikita Khrushchev gave Crimea to Ukraine.
The 100th Anniversary of the Ukrainian union with Russia was celebrated in Crimea.
The anniversary of the union between the two countries may or may not have been celebrated in Crimea. 
( z1 celebrate :ARG1 ( z2 anniversary :topic ( z3 union :ARG1 ( z4 country :name ( z5 name :op "Ukraine" ) ) :ARG2 ( z6 country :name ( z7 name :op "Russia" ) ) ) :ord ( z8 ordinal-entity :value 100 ) ) :location ( z9 peninsula :name ( z10 name :op "Crimea" ) ) )