Heather Abbott was at the finish line of the Boston Marathon on April 15, 2013, when two bombs went off. One of her feet was severely injured in the blast and was eventually amputated.
Nearly a year later, the 39-year-old human resources specialist from Newport, R.I., was back at the same site, this time with a group of fellow survivors of the bombings who crossed the same finish line Sunday to complete the final stage of a cross-country relay that started four weeks earlier in Santa Monica.
"The whole country seems to be here today," Abbott said while holding the relay baton high at the finish of the One Run for Boston charity relay.
That race was just one of many events planned to commemorate Tuesday's anniversary of the bombings that killed three people -- Martin Richard, Krystle Campbell and Lu Lingzi -- and injured more than 260 others.
Tuesday started with a solemn wreath-laying ceremony at the site of the explosions near the finish line. The families of Richard, Campbell and Lingzi were on hand, as well as that of Massachusetts Institute of Technology police officer Sean Collier, who was killed in the aftermath of the blasts.
Later in the day, a program honoring the victims at Hynes Convention Center is expected to be attended by Vice President Joe Biden, among others. Several survivors are scheduled to speak.
But perhaps the biggest tribute of all will take place several days from now, when thousands will gather on Monday to take part in the 2014 Boston Marathon.
President Obama, who is observing the anniversary with a private moment of silence at the White House, said in a statement that this year's race will “show the world the meaning of Boston Strong as a city chooses to run again.”