It's Memorial Day weekend in the United States, and many Americans are making the most of the holiday, which is sort of an unofficial start to the summer season.

With Covid-19 cases dropping and more than half of all adults vaccinated, there's a renewed sense of optimism and hope in the country. People are making up for lost time, hanging out with friends and family and attending events.

More than 37 million people were expected to travel over the holiday weekend -- a big boost from last year's record low, according to AAA.

Here are some of the scenes we're seeing across the nation:

Bugler David Bonczkiewicz plays with the honor guard Monday at the National Memorial Cemetery of Arizona.
Bugler David Bonczkiewicz plays with the honor guard Monday at the National Memorial Cemetery of Arizona.
Thomas Hawthorne/The Republic/Imagn
President Joe Biden delivers an address at Arlington National Cemetery on Monday. "We owe the honored dead a debt we can never fully repay," he said in <a href="https://www.cnn.com/2021/05/31/politics/biden-memorial-day/index.html" target="_blank">his speech.</a> "We owe them our whole souls. We owe them our full best efforts to perfect the union for which they died."
President Joe Biden delivers an address at Arlington National Cemetery on Monday. "We owe the honored dead a debt we can never fully repay," he said in his speech. "We owe them our whole souls. We owe them our full best efforts to perfect the union for which they died."
Mandel Ngan/AFP/Getty Images
Army Capt. Darren M. Cinatl touches the headstone of his friend Andrew Joseph Baddick at Arlington National Cemetery.
Army Capt. Darren M. Cinatl touches the headstone of his friend Andrew Joseph Baddick at Arlington National Cemetery.
Jose Luis Magana/AP
New York Mayor Bill de Blasio speaks during the Intrepid Sea, Air & Space Museum's annual Memorial Day ceremony in New York.
New York Mayor Bill de Blasio speaks during the Intrepid Sea, Air & Space Museum's annual Memorial Day ceremony in New York.
Kena Bentancur/AFP/Getty Images
American flags are placed next to the headstones in Arlington National Cemetery.
American flags are placed next to the headstones in Arlington National Cemetery.
Samuel Corum/Getty Images
Veteran Tim Chambers salutes motorcyclists participating in the "Rolling to Remember" event in Washington, DC, on Sunday, May 30.
Veteran Tim Chambers salutes motorcyclists participating in the "Rolling to Remember" event in Washington, DC, on Sunday, May 30.
Olivier Douliery/AFP/Getty Images
People visit the Vietnam Veterans Memorial in Washington, DC, on Sunday.
People visit the Vietnam Veterans Memorial in Washington, DC, on Sunday.
Olivier Douliery/AFP/Getty Images
A boy makes his way through the aerial ropes course at Harpers Ferry Adventure Center in Hillsboro, Virginia, on Sunday.
A boy makes his way through the aerial ropes course at Harpers Ferry Adventure Center in Hillsboro, Virginia, on Sunday.
Hannah Beier/Reuters
Fans watch the Indianapolis 500 auto race on Sunday. This year's event was billed as the most-attended sporting event since the pandemic's start, with the 135,000 available tickets quickly selling out.
Fans watch the Indianapolis 500 auto race on Sunday. This year's event was billed as the most-attended sporting event since the pandemic's start, with the 135,000 available tickets quickly selling out.
Darron Cummings/AP
People dance on a boat in Chicago on Sunday.
People dance on a boat in Chicago on Sunday.
Shafkat Anowar/AP
People visit the Coney Island boardwalk as rain falls in New York on Sunday.
People visit the Coney Island boardwalk as rain falls in New York on Sunday.
Kena Bentancur/AFP/Getty Images
Hot-air balloons dominated the field Sunday in front of the National World War I Museum and Memorial in Kansas City, Missouri.
Hot-air balloons dominated the field Sunday in front of the National World War I Museum and Memorial in Kansas City, Missouri.
Charlie Riedel/AP
People walk along the Santa Monica Pier in California on Saturday, May 29.
People walk along the Santa Monica Pier in California on Saturday, May 29.
Damian Dovarganes/AP
Elias Loosen plants a flag Saturday as part of the War Memorial Center's Field of Flags community event in Milwaukee.
Elias Loosen plants a flag Saturday as part of the War Memorial Center's Field of Flags community event in Milwaukee.
Ebony Cox/Milwaukee Journal Sentinel/USA Today Network
Tubers make their way to the lower Salt River in Arizona on Saturday.
Tubers make their way to the lower Salt River in Arizona on Saturday.
Cheryl Evans/The Republic/Imagn Content Services, LLC
Air Force veteran Larry Bustetter, left, and Army veteran Henry Knebel salute after placing flags at the Los Angeles National Cemetery on Saturday.
Air Force veteran Larry Bustetter, left, and Army veteran Henry Knebel salute after placing flags at the Los Angeles National Cemetery on Saturday.
Myung J. Chun/Los Angeles Times/Getty Images
Motorcyclists wait for traffic along North Ocean Boulevard in Myrtle Beach, South Carolina.
Motorcyclists wait for traffic along North Ocean Boulevard in Myrtle Beach, South Carolina.
Sean Rayford/Getty Images
People ride a roller coaster at the pier in Santa Monica, California, on Saturday.
People ride a roller coaster at the pier in Santa Monica, California, on Saturday.
Damian Dovarganes/AP
A large crowd gathers to watch a street performance in New York's Times Square on Saturday.
A large crowd gathers to watch a street performance in New York's Times Square on Saturday.
Alexi Rosenfeld/Getty Images
People ride escalators at Atlanta's Hartsfield-Jackson International Airport on Friday, May 28.
People ride escalators at Atlanta's Hartsfield-Jackson International Airport on Friday, May 28.
Will Lanzoni/CNN
Volunteers place flags at the Iowa Veterans Cemetery in Adel, Iowa, on Friday.
Volunteers place flags at the Iowa Veterans Cemetery in Adel, Iowa, on Friday.
Brian Powers/The Register/USA Today Network
People enjoy the boardwalk Friday in Wildwood, New Jersey.
People enjoy the boardwalk Friday in Wildwood, New Jersey.
Spencer Platt/Getty Images
Jacqueline Blair hangs ribbons on flags Friday at the Field of Honor in Idaho Falls, Idaho. A thousand flags will be on display at the Russ Freeman Park through Memorial Day.
Jacqueline Blair hangs ribbons on flags Friday at the Field of Honor in Idaho Falls, Idaho. A thousand flags will be on display at the Russ Freeman Park through Memorial Day.
John Roark/The Idaho Post-Register/AP
Travelers pass through the concourse Friday at Ronald Reagan Washington National Airport in Arlington, Virginia.
Travelers pass through the concourse Friday at Ronald Reagan Washington National Airport in Arlington, Virginia.
Alex Wong/Getty Images
Beachgoers watch as US Marine helicopters practice maneuvers Friday for an air and sea show in Miami Beach, Florida.
Beachgoers watch as US Marine helicopters practice maneuvers Friday for an air and sea show in Miami Beach, Florida.
Joe Raedle/Getty Images
A US soldier places a flag as part of the Flags In ceremony at Arlington National Cemetery on Thursday, May 27. More than 1,000 service members placed flags in front of more than 260,000 headstones.
A US soldier places a flag as part of the Flags In ceremony at Arlington National Cemetery on Thursday, May 27. More than 1,000 service members placed flags in front of more than 260,000 headstones.
Kevin Lamarque/Reuters
People ride along the boardwalk in Wildwood, New Jersey, on Thursday.
People ride along the boardwalk in Wildwood, New Jersey, on Thursday.
Spencer Platt/Getty Images
Vehicles head east out of Los Angeles on Interstate 10 in Alhambra, California, on Thursday. More than 37 million people were expected to travel 50 miles or more from home between Thursday and Monday, according to AAA.
Vehicles head east out of Los Angeles on Interstate 10 in Alhambra, California, on Thursday. More than 37 million people were expected to travel 50 miles or more from home between Thursday and Monday, according to AAA.
Frederic J. Brown/AFP/Getty Images