An Afghan boy pushed a bicycle for his brother in Kabul, Afghanistan on Wednesday. Cycling is growing in popularity in Afghanistan despite harsh conditions at times and a lack of parts or supplies to make repairs. The Afghanistan Cycling Federation, which started as a three person team, has grown to more than 40 men and women that train three times a week in Kabul. A relief organization, Afghan Amputee Bicyclists for Rehabilitation and Recreation, created in 1995 promotes cycling as a means of mobility, income and survival for those who have been victims of mine accidents. Rafiq Maqbool/AP
A pack of riders raced near Aigle during the fifth and final stage of the Tour de Romandie on May 4. The race runs in the Romandie region in the French-speaking region of Switzerland, and ends in the hilly region of Lausanne. The race begain in 1947 to coincide with the 50-year celebration of the Swiss Cycling, the national governing body of cycle racing in Switzerland. A typical 130-pound cyclist burns 402 calories while pedaling 14 miles in an hour, and a 180-pound cyclist burns 540 calories. One of the most well known cylcing races, the Tour de France, will take place in July. Denis Balibouse/Reuters
May is national bike month in the US, and the League of the American Bicyclists is promoting 'Bike-to-Work-Week' from May 12-16 to encourage people to commute by bike and not by car if possible. Chris Bosley made his way through a traffic circle in Coeur d'Alene, Idaho on his way to a meeting of the city's pedestrian bike committee on May 14. Mr. Bosley bikes to work on a regular basis. Jerome A. Pollos/Coeur d'Alene/AP
A women collected her bike from a parking lot outside a subway station in Beijing, China. Rising gasoline prices, growing awareness of environmental issues, and a increased popularity in cycling has lead to a surge in demand for bikes. China has the largest fleet of bikes, with nearly a half billion Chinese cyclists. Reinhard Krause/Reuters
Italy's Danilo Di Luca (r.) rides hard near a track marshall during the sixth stage of the 91st Giro d'Italia cycling race from Potenza to Peschici, Italy, on May 15. This stage of this Tour de France-inspired race is 247 kilometers and was first run on May 13, 1909. The Giro d'Italia is part of the Triple Crown of Cycling along with the Tour de France and the World Cycling Championship. Giampiero Sposito/Reuters
A Palestinian boy rode his bike pulling a trailer loaded with cooking gas canisters near a gas station in Gaza on May 13. Since the seizure of the territory by Hamas, Gaza has been virtually sealed off by Israel and Egypt, creating economic hardships for the 1.4 million residents affected by the blockade. In April, Gaza's fuel was cut off after a Palestinian attack on a distribution terminal, forcing people to use cooking oil to power their cars, or find alternative means of transport. Hatem Moussa/AP
Andrew Batjiaka, a volunteer at the Bike Co-op at Oberlin College, maneuvered through the graveyard area inside the co-op where many old bikes that students have left behind are kept. Parts are taken off the broken bikes and are reused to fix or make new bikes. According to the US Census Bureau, Oberlin ranked 12th in the United States in percentage of residents who commute to work or school on a bicycle. Tracy Boulian/The Plain Dealer/AP
A mother and a child were given a ride on a bicycle in Zalewa, a small town outside of Blantyre, southen Malawi. Malawians can make $5 a day from transporting people on bicycles, in a nation where more than half of its 13 million people live on less a dollar a day. Siphiwe Sibeko/Reuters
Jesse Beam took a ride on a solar powered assisted bike during the Green Grand Prix road rally for alternate-fuel vehicles and hubrids in Watkins Glen, NY. National bike month is May in the US, and the Green Grand Prix emphasizes energy independence and a cleaner environment. Motor vehicle emissions represent 31 percent of total carbon dioxide, 81 percent of carbon monoxide and 49 percent of nitrogen oxides released in the US, according to the League of American Bicyclists. David Duprey/AP
Cyclists rode their bikes through blooming dandelions on a sunny day in Glarus, Switzerland. The SwitzerlandMobility Foundation was started in 1993 by cycling enthusiasts who wanted to create a network of national cycle-tour routes across the country. The objective is to coordinate and promote non-motorized traffic. Eddy Risch/KEYSTONE/AP
A man cycled with his daughter past a sign advertising gasoline at a BP station in Miami Beach, Fla on May 5. Oil futures surged to a new record over $120 a barrel, raising concerns about even high prices for gasoline. About 41.3 million Americans (20 percent), used a bicycle for transportation in the 30 days measured in a 2000 Omnibus Household Survey, and a bike is the second most preferred form of transportation after the automobile, and ahead of public transportation. Lynne Sladky/AP
Members of the Follow the Women Foundation rode bicycles during a tour in Amman, Jordan on May 9. About 400 women from more than 30 countries are participating in the event to cycle through Middle Eastern countries to promote peace and empower women in the region. The first Pedal for Peace, Follow the Women campaign was in 2004. 'Women do not traditionally cycle in the Middle East, so the sight of a large female-only group attracts huge interest,' said founder Detta Regan. Muhammad Hamed/Reuters
The extremist group al-Shabab attacked the AU headquarters in Mogadishu; at least five of the militants were killed.
ByAbdi Guled, Associated Press
Gunmen attacked the African Union's main base in the capital, Mogadishu, on Thursday leading to an exchange of gunfire between militants and soldiers that left at least five militants dead, an official with the mission in Somalia said.