(CNN) The idea of being buried next to a friend likely never crosses the mind of most Americans.

But for Sen. John McCain and Adm. Chuck Larson and many others, the decision to rest eternally by the side of a fellow military academy graduate is not an unusual choice.

McCain, who died just over a week ago at 81, was buried Sunday afternoon next to Larson, his US Naval Academy classmate and friend, near a bluff that overlooks the confluence of the Severn River and College Creek in Annapolis, Maryland. The ceremony at the academy's nearly seven-acre cemetery was private.

The cemetery reflects other such friendships.

Although he has not been able to find documents, James Cheevers, retired curator at the Naval Academy Museum, said he believes Cushing, who died at 32 nearly a decade after the war, may have had his pals reinterred in Annapolis so they could be together.

Others who have chosen to be beside friends include World War II Fleet Adm. Chester Nimitz, who is buried near high-ranking academy comrades at Golden Gate National Cemetery just outside San Francisco.

"This is not uncommon," said Cheevers.

Larson and McCain were classmates in the graduating class of 1958. But while Larson graduated toward the top of the class, McCain graduated fifth from the bottom.

The two forged a bond in youth that withstood the test of time, personal and family sacrifice and, in McCain's case, spending more than five years as a prisoner of war in North Vietnam.

Sarah Larson, who was married to Chuck for 52 years before he died in 2014, said she first learned 20 years ago that McCain and her husband wanted to be buried next to one another. The admiral, who twice served as superintendent at the academy, had selected four plots for the officers and their spouses.

"Chuck came home one day and he said, 'I picked out my grave, and I went 'Oh, OK,'" Sarah Larson told CNN's John Berman in an interview on "New Day" on Friday. "So I just said, 'That's fine, good,' and he said, 'By the way, John is going to be next to me.'"

Photos: In pictures: The John McCain memorials Photos: In pictures: The John McCain memorials The casket of US Sen. John McCain lies in state at the US Capitol on Friday, August 31. Hide Caption 1 of 47 Photos: In pictures: The John McCain memorials McCain's wife, Cindy, lays her head on her husband's casket during his burial service on Sunday. Hide Caption 2 of 47 Photos: In pictures: The John McCain memorials McCain's son Jimmy hugs his brother Jack during the private burial service. Hide Caption 3 of 47 Photos: In pictures: The John McCain memorials Sailors follow McCain's casket along the procession route at the US Naval Academy. McCain graduated from the academy in 1958 and served in the Navy until 1981. Hide Caption 4 of 47 Photos: In pictures: The John McCain memorials McCain's casket is brought out of a chapel during a private funeral service at the US Naval Academy. Hide Caption 5 of 47 Photos: In pictures: The John McCain memorials McCain's casket is carried out of the chapel Sunday. Hide Caption 6 of 47 Photos: In pictures: The John McCain memorials Sailors participate in Sunday's funeral service. Hide Caption 7 of 47 Photos: In pictures: The John McCain memorials Cindy McCain looks on as her husband's casket is carried after a funeral service Saturday at the Washington National Cathedral. Hide Caption 8 of 47 Photos: In pictures: The John McCain memorials McCain's casket is carried out of the National Cathedral at the end of Saturday's service. Hide Caption 9 of 47 Photos: In pictures: The John McCain memorials Former President Barack Obama delivered a eulogy and praised McCain's efforts to push the nation to rise above "mean and petty" politics. "So much of our politics, our public life, our public discourse can seem small and mean and petty, trafficking in bombast and insult, and phony controversies, and manufactured outrage," Obama said. "It's a politics that pretends to be brave and tough, but in fact is born of fear. John called on us to be bigger than that. He called on us to be better than that." Hide Caption 10 of 47 Photos: In pictures: The John McCain memorials Former President George W. Bush spoke about his relationship with McCain and how their rivalry melted away over time. Bush defeated McCain to become the GOP's presidential nominee in 2000. "Back in the day, he could frustrate me. And I know he'd say the same thing about me. But he also made me better," Bush said. Hide Caption 11 of 47 Photos: In pictures: The John McCain memorials From left, former President George W. Bush; former first lady Laura Bush; former President Bill Clinton; former Secretary of State Hillary Clinton; former Vice President Dick Cheney; Cheney's wife, Lynne; and former Vice President Al Gore sing during the memorial service Saturday. Hide Caption 12 of 47 Photos: In pictures: The John McCain memorials Former Secretary of State Henry Kissinger said the world will be lonelier without McCain. Hide Caption 13 of 47 Photos: In pictures: The John McCain memorials Meghan McCain pays tribute to her father during the service. "We gather here to mourn the passing of American greatness, the real thing, not cheap rhetoric from men who will never come near the sacrifice he gave so willingly, nor the opportunistic appropriation of those who live lives of comfort and privilege while he suffered and served," she said. Hide Caption 14 of 47 Photos: In pictures: The John McCain memorials Meghan McCain and her mother embrace as the senator's casket arrives at the National Cathedral. Hide Caption 15 of 47 Photos: In pictures: The John McCain memorials From left, former President Barack Obama, former first lady Michelle Obama, former Vice President Al Gore, former President George W. Bush, former first lady Laura Bush and former Secretary of State Hillary Clinton arrive for Saturday's memorial service. Hide Caption 16 of 47 Photos: In pictures: The John McCain memorials From left, former Defense Secretary William Cohen, former New York Mayor Michael Bloomberg, former Vice President Joe Biden and actor Warren Beatty serve as pallbearers. Hide Caption 17 of 47 Photos: In pictures: The John McCain memorials A military honor guard carries McCain's casket at the Washington National Cathedral. Hide Caption 18 of 47 Photos: In pictures: The John McCain memorials Rhonda Zuck, left, and her husband, Tim, drove from Racine, Wisconsin, for a wreath-laying ceremony at the Vietnam Veterans Memorial. Hide Caption 19 of 47 Photos: In pictures: The John McCain memorials Cindy McCain is accompanied by White House Chief of Staff John Kelly, left, and Defense Secretary Jim Mattis as she lays a wreath at the Vietnam Veterans Memorial on Saturday. Hide Caption 20 of 47 Photos: In pictures: The John McCain memorials A visitor becomes emotional while paying respects to the late senator as he lied in state Friday in the US Capitol's rotunda. Hide Caption 21 of 47 Photos: In pictures: The John McCain memorials Cindy McCain prays at her husband's casket on Friday. Hide Caption 22 of 47 Photos: In pictures: The John McCain memorials Former US Sen. Joe Lieberman and his wife, Hadassah, pay their respects during the viewing at the Capitol. Hide Caption 23 of 47 Photos: In pictures: The John McCain memorials Vice President Mike Pence delivers remarks at the US Capitol ceremony on Friday. To Pence's right are McCain's 106-year-old mother, Roberta, and McCain's daughter Meghan. "Let me say to all those gathered and his beloved family: On behalf of a grateful nation, we will ever remember that John McCain served his country and John McCain served his country honorably," Pence said. Hide Caption 24 of 47 Photos: In pictures: The John McCain memorials Members of the McCain family pay their respects on Friday. Hide Caption 25 of 47 Photos: In pictures: The John McCain memorials US Sen. Lindsey Graham touches McCain's casket. Graham took to the Senate floor Tuesday to give an emotional farewell to his friend and colleague. Hide Caption 26 of 47 Photos: In pictures: The John McCain memorials Members of the public file through the Capitol rotunda to pay their respects. Hide Caption 27 of 47 Photos: In pictures: The John McCain memorials McCain's casket is carried up the Capitol steps. A storm broke out at the very moment McCain's casket was carried in. Hide Caption 28 of 47 Photos: In pictures: The John McCain memorials McCain served in Congress for more than 30 years. Hide Caption 29 of 47 Photos: In pictures: The John McCain memorials Among the guests Friday were actors Annette Bening, back left, and Warren Beatty. Hide Caption 30 of 47 Photos: In pictures: The John McCain memorials Navy sailors salute as McCain passes by in Washington. Hide Caption 31 of 47 Photos: In pictures: The John McCain memorials A man salutes as a hearse carrying McCain's casket travels to a memorial service at the North Phoenix Baptist Church on Thursday. Hide Caption 32 of 47 Photos: In pictures: The John McCain memorials Former Vice President Joe Biden wipes away a tear while giving a tribute to McCain at Thursday's memorial service in Phoenix. "I always thought of John as a brother," Biden said. "We had a hell of a lot of family fights. We go back a long way." Hide Caption 33 of 47 Photos: In pictures: The John McCain memorials Pro football player Larry Fitzgerald, a friend of McCain's, speaks at the late senator's memorial service on Thursday. McCain "didn't judge individuals based on the color of their skin, their gender, their backgrounds, their political affiliations, or their bank accounts," Fitzgerald said. "He evaluated them on the merits of their character and the contents of their hearts." Hide Caption 34 of 47 Photos: In pictures: The John McCain memorials McCain's casket arrives at the North Phoenix Baptist Church on Thursday. Hide Caption 35 of 47 Photos: In pictures: The John McCain memorials McCain's family watches as his casket is moved from a hearse on Thursday. From left are McCain's son Doug, his son Jimmy, his daughter Meghan, his son Jack, his wife Cindy, his daughter Bridget, his daughter Sidney and his son Andrew. Hide Caption 36 of 47 Photos: In pictures: The John McCain memorials People in Phoenix watch a motorcade carrying McCain's casket on Thursday. Hide Caption 37 of 47 Photos: In pictures: The John McCain memorials Meghan McCain cries next to her father's casket during a memorial service at the Arizona State Capitol on Wednesday. Hide Caption 38 of 47 Photos: In pictures: The John McCain memorials McCain's wife, Cindy, lays her head on his casket Wednesday. Hide Caption 39 of 47 Photos: In pictures: The John McCain memorials US naval cadets walk past McCain's casket on Wednesday. Hide Caption 40 of 47 Photos: In pictures: The John McCain memorials People wait in line for their chance to pay their respects at the Arizona State Capitol. Hide Caption 41 of 47 Photos: In pictures: The John McCain memorials A man signs a register before paying tribute to McCain on Wednesday. Hide Caption 42 of 47 Photos: In pictures: The John McCain memorials Cindy McCain, front left, sits with her children Jack, Jimmy and Meghan during the service in Phoenix. From left to right in the second row are Doug and Sidney, John McCain's children from his first marriage, and the McCains' adopted daughter, Bridget. Hide Caption 43 of 47 Photos: In pictures: The John McCain memorials People stand during Wednesday's memorial service. In the last 40 years, only two other people have lain in state at the State Capitol: state Sen. Marilyn Jarrett in 2006, and Olympic gold medalist Jesse Owens in 1980. Hide Caption 44 of 47 Photos: In pictures: The John McCain memorials McCain's casket is carried into the Arizona State Capitol. Hide Caption 45 of 47 Photos: In pictures: The John McCain memorials Cindy McCain and her son Jack follow military personnel carrying the casket. Hide Caption 46 of 47 Photos: In pictures: The John McCain memorials Members of Arizona law enforcement wait for the start of the memorial service in Phoenix. Hide Caption 47 of 47

After graduation, McCain and Larson earned their wings together at the Naval Air Station Pensacola and shared living quarters during their advanced flight training at NAS Corpus Christi, before Larson entered submarine service.

"Chuck has his wingman back now," Sarah Larson said.

About 500 midshipmen lined the route from the academy chapel to the cemetery Sunday, as McCain's casket was carried by a horse-drawn caisson. Relatives walked behind. Navy jets executed a "missing man" formation in the blue sky in honor of the former military aviator.

In October 2017, just three months after his cancer diagnosis was made public, McCain spoke at the Naval Academy and began his talk by admitting to breaking rules during his time there.

"My superiors didn't hold me in very high esteem in those days," the senator said. "Their disapproval was measured in the hundreds of miles of extra duty I marched in my time here."

Cheevers said the midshipmen "love him (and) anybody that gave the academy a hard time, particularly in the plebe year."

(Cushing -- the Civil War hero -- also was known as a prankster and maverick. But, unlike McCain, he was forced to leave the academy and did not graduate.)

The McCain procession on Sunday passed other US Navy heroes, many of whom died in combat or in military accidents. Among those buried at the academy are Adm. James Stockdale and Fleet Adm. Ernest King, chief of naval operations during World War II.

To some, it may be ironic that McCain was laid to rest at an institution with which he admitted to having a "complicated relationship."

Cheevers, the retired museum curator, said the Arizona senator's description of his time at Annapolis speaks for many academy graduates.

"Most of them ... find it very difficult while they are there to accept the place, to be accustomed to it and be happy," Cheevers said. He has observed that most form a strong attachment to the academy after they leave it.

Over the years, McCain came to appreciate his Naval Academy education and lessons about courage, humility and sacrifice.

"My appreciation for those lessons and for the friendships I made here bring me back often," he told midshipmen last year. "So does my gratitude for the life of adventure the Naval Academy prepared me for, and for the privilege of being a bit player in the story of America that the Navy made possible."