2011 was the year of Arab Spring, of Hurricane Irene, of the dismantling of Don't Ask, Don't Tell, and of countless political, cultural and scientific advances and upheavals. It was also a year of photos.

From the UC Davis pepper spraying to the death of Osama bin Laden, relive 2011 through some of the most powerful photos of the year.

These images, taken by professional Reuters photographers and by ordinary citizens around the world, helped to capture, in a single moment, some of the pivotal turning points of 2011.

See the humanity amid the violence at Tahrir Square in Cairo, Egypt. See soldiers rejoicing at the first gay pride parade hosted by out servicemen in the U.S. See the wreckage of the tornadoes that swept the American South this spring, and the rise of the Occupy Wall Street and Tea Party movements.

Most of all, see the people captured in these images, and the photographers behind them. As we approach 2012, look back on 2011, and see the beauty and the tragedy of the past 340 days.

911, Ten Years Later
Ten years after the Sept. 11 terror attacks, Robert Peraza pauses by his son Robert David's name at the 9/11 memorial. Reuters/Pool
Haboob
A monstrous dust storm tore through Phoeniz, Ariz. in July, delaying flights, causing power outages and swallowing the city. The "haboob" dust cloud reached heights of 8,000-10,000 feet, and in some areas about 50 miles wide. danbryant.com
Gaddafi Withdraws
A female rebel fighter fires an AK-47 in the air to celebrate the withdrawal of Libyan leader Muammar Gaddafi's forces from Benghazi during Arab Spring. Reuters / GORAN TOMASEVIC
Azerbaijan Protests
A policeman detains an opposition activist on March 12, 2011. Azerbaijan police detained more than 30 activists of the opposition Musavat Party when its members took to the street of Baku to protest against the ruling elite. Reuters
Osama Bin Laden
Members of Obama's national security team receive news that Osama bin Laden has been killed on May 1, 2011. Reuters / HANDOUT
Annual Hurricane Conference In Florida
Hurricane is one of the terrifying natural disasters; it has claimed several lives and destroyed several properties. Reuters
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