sentences:  In 1967, a memorial to the victims of the Armenian Genocide was built at the Tsitsernakaberd hill above the Hrazdan gorge in Yerevan.This occurred after mass demonstrations took place on the tragic event's fiftieth anniversary in 1965.During the Gorbachev era of the 1980s, with the reforms of Glasnost and Perestroika, Armenians began to demand better environmental care for their country, opposing the pollution that Soviet-built factories brought.