Norway is commemorating the first anniversary of the brutal attacks that claimed the lives of 77 people and injured 242 others, with a series of solemn ceremonies across the country.
Thousands of Norwegians assemled at the sites of massacre in Oslo and the island of Utoeya to remember the victims of the tragedy.
Norway's Prime Minister Jens Stoltenberg laid a wreath at the memorial in Central Oslo and said: "The bomb and the shots were intended to change Norway. People responded by embracing our values. He failed, the people won."
"Let us honour the dead by being happy about the life they had, and the life we share," he added.
Church services, concerts and memorial services are being held across the country.
"The light shines in the darkness; darkness hasn't been able to overcome it," said Bishop Helga Haugland Byfuglien told the gathering during a special mass in Oslo Cathedral.
Stoltenberg will then address young members of his Labour Party at an event on the island of Utoeya and meet with the families of the victims. He is also expected to attend a concert outside Oslo City Hall.
Bruce Springsteen and the Norwegian folk singer Lillebjoern Nilsen are among the musicians expected to appear at the concert, according to an AFP report.
On 22 July, 2011, right-wing extremist Anders Behring Breivik detonated a bomb near a government building in Oslo, killing eight people. Breivik then travelled to Utoeya to carry out a shooting spree at a summer camp for young people organised by the ruling Labour Party.
He killed 69 people on the island. Most were teenagers; the youngest victim was 14 years old.
Shortly after the massacre, the prime minister reacted to the killing by saying that Norway would respond to the bloodbath with "more democracy, more openness and more humanity, but never naivety".
The 33-year-old Breivik's 10-week trial came to an end in June. A verdict is expected on 24 August.