"It's a way for us to say thank you," said Patriot Guard member Bill Bastas.
For hours on Tuesday, the Patriot Guard lined the streets of East Austin and portions of the cemetery for Kyle's private burial. They created a wall of red, white and blue to give their condolences to the Kyle family as they entered the cemetery.
"I didn't know him personally, but he was an exceptional young man," said Navy veteran Emit Stover. "Just paying tribute to a brother."
Patriot Guard members also escorted the 200-mile procession from Midlothian, Texas, to Austin. Among them were several Navy veterans.
"It's a devastating loss. He survived four tours and was the most accomplished sniper in the United States," said Navy veteran Sean Hanna. "His death is absolutely tragic and heartbreaking."
After a 200-mile journey, former Navy SEAL sniper Chris Kyle was buried Tuesday in Austin as his family members and fellow SEALs looked on amid the sounds of drums and bagpipes.
A giant Texas flag flew at half-staff over the Texas State Cemetery as Kyle was laid to rest. Kyle, considered to be the deadliest sniper in U.S. military history, was killed along with a friend earlier this month while at a North Texas gun range.
A white hearse carrying Kyle's flag-draped coffin was among 200 vehicles in a procession that left Tuesday morning from Kyle's hometown of Midlothian, about 25 miles southwest of Dallas, to travel to Austin. Many motorists pulled to the side of roads to watch the procession that included motorcycles, motor coaches, police cruisers and other vehicles.
It briefly came to a halt when three motorcycles in the procession went down just north of Austin, sending two people to the hospital with non-life threatening injuries, said Belton police Sgt. Larry Berg. He said Navy SEALs in the procession rendered first aid until authorities arrived.
"Heroes on duty and heroes off duty, certainly," Berg said.
Larry Key, one of about 100 Patriot Guard Riders who gathered for the event, said he came in tribute to Kyle's service. Kyle, 37, completed four tours in Iraq and wrote the best-selling book "American Sniper."
"It's our way of honoring Chris and his family," said Key, a Vietnam veteran from Denton.
In Austin, hundreds of people gathered on roads stretching nearly a mile from the cemetery. Many who came to watch the procession were combat veterans in leather jackets who parked their motorcycles three wide around the permitted area of the gravesite. Others were businessmen in suits on their lunch break from the nearby Capitol, families with strollers and at least one jogger taking a break from an afternoon run.
Mike Lamb, 24, stood about a half-mile from the cemetery wearing a mustard yellow Marine Corps shirt and holding a sign that read, "Fair Winds and Calm Seas Frogman! R.I.P."
Lamb said he called in sick from work to see the procession. Because of that, he was at first reluctant to give his name. But he then rationalized that it didn't matter. Next month, Lamb is leaving for boot camp in the Marines.
"(Kyle) was the last person that I would have expected to end up like that," Lamb said. "Because he was so into Wounded Warriors and helping soldiers with (post-traumatic stress disorder). He was a warrior overseas and at home."
An Iraq War veteran, Eddie Ray Routh, 25, has been charged in the killings of Kyle and his friend Chad Littlefield. Routh's brother-in-law told authorities that Routh had recently been diagnosed with PTSD.
Authorities say Kyle, Littlefield and Routh arrived together at the Rough Creek Lodge shooting range, about 50 miles southwest of Fort Worth, on the afternoon of Feb. 2. Routh later fled in Kyle's truck.
According to a search warrant, Routh told his sister and brother-in-law that the men "were out shooting target practice and he couldn't trust them so he killed them before they could kill him."
On Monday, some 7,000 people attended a two-hour memorial service for Kyle at Cowboys Stadium in Arlington. Kyle's coffin was placed at the Dallas Cowboys' star at midfield.
His widow, Taya Kyle, told the crowd she was broken but that her family would "put one foot in front of the other" to get through their grief. She said she told her two children that they will remember Kyle's silly side, Texas twang and the prayers they prayed together.
Littlefield's funeral was held Friday in Midlothian. Afterward, Littlefield's relatives said the outing with Routh was intended to be therapeutic.
The Associated Press contributed to this report.