"This is a tragic and yet heroic page in our history," St. Petersburg Governor Valentina Matviyenko said in a congratulatory message. "The defenders and residents of the city underwent unthinkable trials - starvation, bitter cold, bombardments. Our city lived on, fought and worked."
The Siege of Leningrad, now St. Petersburg, lasted from September 1941 to January 1944, when food and military supplies were brought to the city via Lake Ladoga, the only route named the Road of Life that connected the city with the mainland.
During the warm season people were ferried to the mainland, and in winter - carried by trucks that crossed the frozen lake under constant enemy bombardment. In January 1943, the siege was broken and a year later, on January 27, 1944 it was fully lifted.
At least 800,000 people died in Leningrad during the siege, according to official figures.
In January 1942, in the midst of an unusually cold winter, the city's food rations reached an all time low of only 125 grams (about 1/4 of a pound) of bread per person a day. In just two months, 200,000 people died in Leningrad of cold and starvation.
The date is widely celebrated in the city and across the country. Wreath-laying ceremonies are held at St. Petersburg's memorial cemeteries, attended by blockade survivors, WWII veterans and city officials. Charity concerts, exhibitions and other events are also on the program.
President Dmitry Medvedev, who was born in St. Petersburg, is on a visit to the city. On Tuesday, he laid flowers at a war monument at the Piskaryovskoy Memorial Cemetery, the resting place for over 500,000 people who perished during the siege, and attended a reenactment of the WWII battle that ended the siege.
City residents will switch off electric lights at dusk (7 p.m.) and place lighted candles on windowsills as part of events to commemorate the anniversary.
The anniversary events and celebrations will round off with a firework display near the St. Peter and Paul Fortress on the River Neva.