The cathedral is located in historic old Havana
Cuba's first Russian Orthodox church has been consecrated in the capital, Havana, in a ceremony attended by Cuban President Raul Castro.
The consecration was part of a day of activities to celebrate improving Cuba-Russia ties, which were damaged after the Soviet Union collapsed in 1991.
The USSR had been Cuba's main benefactor during the Cold War.
Russian diplomats and members of Cuba's small Russian community crowded into the cathedral for the service.
The gold-domed Our Lady of Kazan cathedral was built over the last four years, discreetly and slowly, mirroring the development of ties between Havana and Moscow, says BBC Mundo's correspondent in Cuba, Fernando Ravsberg.
Most of the construction of the church, which is located in historic old Havana surrounded by Spanish colonial architecture, was paid for by the Cubans.
Metropolitan Kirill said Russian-Cuban ties had survived difficult times
Mr Castro, dressed in a dark suit and tie, joined the congregation as the cathedral was consecrated but left before the liturgical service began.
Metropolitan Kirill, the head of foreign relations for the Russian Orthodox Church, had travelled from Moscow to perform Sunday's ceremony, accompanied by several government ministers.
"This is a monument to Russian-Cuban friendship and all the efforts that have preserved our relations including the most difficult moments of the Cold War," he said.
For much of that period, Cuba and the USSR were strategic allies, and tens of thousands of Russians were stationed in Cuba, resulting in a number of intermarriages.
Sunday's ceremony also coincided with the anniversary of the Cuban missile crisis in October, 1962, which brought the world to the brink of nuclear war.
Recent good relations began in 2006 and have been steadily improving. Russia is currently Cuba's 10th biggest trading partner.
Moscow's dispute with Washington over US plans for a missile defence shield in Europe have also renewed Russia's interest in Cuba.