Since the ALS Ice Bucket Challenge began three years ago, Pete Frates has built a special bond with the city of Boston and Major League Baseball. That was never more evident than on Tuesday, when the city declared Sept. 5 to be Pete Frates Day.

On the steps of City Hall, Boston mayor Marty Walsh was joined by MLB Commissioner Rob Manfred, Red Sox president and chief executive officer Sam Kennedy, Red Sox chairman Tom Werner and the Frates family to celebrate the day.

"It showed you can have a ripple effect that reaches far beyond any one individual," Walsh said of the Ice Bucket Challenge. "Pete's changed our city for the better and has made a difference in countless numbers of people's lives and helps us remember that in the end, we are one family."

Frates, who grew up in Beverly, Mass., and played college baseball at Boston College, was diagnosed with ALS in March 2012. Soon after that, Frates began doing everything he could to raise awareness about the disease, efforts which culminated in the Ice Bucket Challenge. Since his and other videos went viral in summer '14, more than $220 million has been raised to fight ALS.

"It is a well-deserved honor for a great American," Manfred said. "Everyone knows about the bond between baseball and ALS because of Lou Gehrig and other great players, and because of that bond, we try to be supportive of Pete, his family and the foundation."

The celebration coincides with the book release of "The Ice Bucket Challenge: Pete Frates and the Fight against ALS" by Casey Sherman and Dave Wedge. Half of the proceeds from the book will go to the Frates family.

Julie Frates, Pete's wife, said the entire family is humbled by the honor.

"Anyone who knows Pete knows how much the city of Boston means to him. Without this city, there would be no Ice Bucket Challenge phenomenon," Julie said. "We are so proud to call Boston home and humbled by a day like today."

The bucket Frates used for his own Ice Bucket Challenge at Fenway Park on Aug, 14, 2014, was donated to the Baseball Hall of Fame in Cooperstown, N.Y., earlier this spring, along with memorabilia from his playing days at Boston College.

"Pete belongs on the Mount Rushmore of sports in Boston with Larry Bird, David Ortiz, Tom Brady and Bobby Orr and all the greats, for his fearlessness and courage with which he's attacked this disease," Kennedy said. "We are all in awe of Pete."