Politics Jill Biden Celebrates 70th Birthday with a 'Quiet Day' — and Some Biking — with Joe at Their Beach House The first lady just finished teaching her first semester since returning to the White House By Sean Neumann Sean Neumann Sean Neumann is a journalist from Chicago, Ill. People Editorial Guidelines Updated on June 3, 2021 03:22 PM Share Tweet Pin Email First Lady Dr. Jill Biden is celebrating her 70th birthday at the beach. She marked her milestone on Thursday and was spending it with President Joe Biden at the first couple's vacation home in Rehoboth Beach, Delaware. "She'll be in Rehoboth having a quiet day with the president," the first lady's spokesman tells PEOPLE. Family and friends were not joining them. Dr. Biden was already at their beach house in Delaware when President Biden, 78, arrived Wednesday night, according to the Associated Press. They are expected to return to Washington, D.C., on Friday, and they have regularly spent downtime from the White House either in their home state of Delaware or at Camp David. The local weather on Thursday was sunny and "warm," with breezy temperatures around 79 degrees, according to a pool report from journalists traveling with the president. Jill Biden Gets Right to Work While Still Teaching — the New First Lady Talks White House Plans First Lady Dr. Jill Biden. JIM WATSON/AFP via Getty From left: President Joe Biden and First Lady Dr. Jill Biden. JIM WATSON/AFP via Getty The Bidens went biking in the early afternoon along the Gordons Pond Trail, in the Cape Henlopen State Park. Some bystanders shouted "Happy Birthday!" and sang to the first lady as she rode by, according to reporters. The president and first lady were photographed smiling and waving to people watching them ride down the trail. The AP reports the couple purchased their beach house in 2017 for $2.7 million. The couple signed an $8 million three-book deal when then-Vice President Biden left office. The home is located just blocks away from the Atlantic Ocean. Vogue described it in 2019 as "a rambling, three-story Colonial painted the color of just-washed denim." "I wanted it to be the kind of place where you can come in in your wet bathing suit and bare feet and I can just take the broom and brush out the sand," Dr. Biden told the magazine then. "And that's what this is. Everything's easy." Outside the front door of the house, a sign reads: "A PROMISE KEPT" Jill Biden. Official White House Photo by Adam Schultz "The promise kept was actually this house!" Dr. Biden told Vogue. "Because he kept saying, 'When I write my book, I'll buy you a beach house.' " Dr. Biden said that she instantly knew the vacation house was the one she wanted as soon as the couple started shopping for homes, but the future president believed it was too expensive so they looked at two dozen more properties. "He loves to look at houses. It's one of his things," Dr. Biden said. What the Bidens Learned from 43 Years of Marriage and Why He Still Gives Her a Corsage From left: President Joe Biden and First Lady Dr. Jill Biden look out the windows of Marine One at they fly over the National Mall in Washington, D.C., on April 2 en route to Camp David. Official White House Photo by Adam Schultz From left: President Joe Biden and First Lady Dr. Jill Biden walk on the Ellipse on May 23 in Washington, D.C. Tasos Katopodis/Getty In addition to celebrating her birthday this week, the first lady will likely be celebrating summer vacation after finishing her latest semester virtually teaching an English course at Northern Virginia Community College. Dr. Biden — or "Dr. B," to her students — won't be teaching over the summer, according to the AP, taking advantage of the semester break to focus on her role as first lady. "I taught all eight years that I was second lady," the first lady told PEOPLE earlier this year. "As Joe knows that's my passion, that's my life."