Vice President Joe Biden and his wife Jill welcomed members from all branches of the military Wednesday morning to kick off the Wounded Warrior Soldier Ride on the South Lawn of the White House.

“Thank you for all that you do to serve our country,” Jill Biden said. “We are a grateful nation.”

Secretary of Defense Robert Gates and Secretary of Veterans Affairs Eric Shinseki also attended the ceremony.

Before sounding a horn to signal the beginning of the race, Biden told the soldiers that their losses were incomprehensible. “However, you all define who we are as a country,” he said. “Thank you from all of America.”

Soldier Ride is a program of the Wounded Warrior Project that provides rehab opportunities for wounded warriors and raises public awareness of challenges facing vets. The four-day cycling event will end in Annapolis Saturday.

–report and photographs by Kate Oczypok