Boston Marks 12th Anniversary of Marathon Bombing with Acts of Service

On April 15, Boston residents came together to mark One Boston Day through kind deeds and quiet remembrance ceremonies. Created in 2015, this yearly tradition brings locals together to help their community while remembering those who died in the 2013 marathon bombing.

At the wreath-laying ceremonies on Boylston Street, Mayor Michelle Wu stood with Lt. Governor Kim Driscoll and victims' families. "Boston is a city built on community... Twelve years ago, we endured a tragedy at the Boston Marathon that shook our city to the core. Rather than come apart, we tapped into the wellspring of love that lives in every one of our neighborhoods," said Wu in a statement.

Martin Richard, Krystle Campbell, and Lu Lingzi lost their lives near the finish line. Later, MIT police Officer Sean Collier and Boston police Officer Dennis Simmonds died in connected events.

Church bells will ring at Old South Church at 2:49 p.m., marking when the first explosion happened. A quiet service gives people time to remember.

Two pressure cooker bombs exploded in the crowd at the 127th Boston Marathon. The explosions hurt hundreds of people watching and running.

Across the city, local groups set up different ways to help - from cleaning neighborhoods to collecting food and giving blood.

Starting in 1897, the Boston Marathon is one of the world's oldest yearly races. The 2013 attack led to major changes in how they handle security.

Three memorials along Boylston Street show where people died. Many visitors stop by these spots to pay tribute.

Volunteer work spreads through Boston's neighborhoods today. Local schools work with businesses to plan charity events.

As people join in helping, city officials keep track of activities on different websites, showing how One Boston Day brings communities together.