This is an Ilyushin Il-28 (Beagle), made into a monument to commemorate its 25 years of service in the Polish air force. This tactical jet bomber was first flown in 1948, and was originally manufactured for the Soviet Air Forces. Total production in the USSR was over 6,300, with another 300 aircraft built in China. It was exported to some 25 countries.
In part, the Cuban missile crisis was about the Russian attempt to station these bombers in Cuba - which was a bit of a joke, given the poor range and bomb load of this aircraft.
Today, it is still in service - as THE nuclear bomber - in the North Korea's air force.