Former U.S. President Barack Obama visited Alexandria National Cemetery to participate in a Memorial Day event

"Thank you @BarackObama for surprising and joining the incredible volunteers at Alexandria National Cemetery today as they work to honor those who made the ultimate sacrifice to ensure our freedoms," Mayor Justin Wilson wrote on Twitter. "Mr. President, you are always welcome in Alexandria!"

Veterans of Foreign Wars Post 609 was cleaning up the military cemetery when they were visited by the 44th President.

"One of the greatest honors of my life has been the privilege of serving as commander in chief, and along with the pride sometimes came heartache and loss," Obama said at the cemetery, according to Military Times. And a sober recognition of the sacrifices that so many Americans and their families have made to preserve our freedom."