Several Chicago-area runners plan to head back to the Boston Marathon this year to participate in the event – a choice they say they made both to support the city and to remember those who were affected by the bombings at the sporting event on April 15, 2013.

Last year marked the first time Deirdre Kilgallon, 56, a Chicago resident who grew up in Glenview, was able to qualify for the Boston marathon after years of training.

But because of the tragic attack, her anticipated visit was unlike anything she could have imagined.

"The whole experience is going to be very emotional," said Kilgallon, who is going back to this year's marathon after not being able to finish it last year.

About four hours into the 2013 Boston Marathon, two pressure-cooker bombs exploded near the finish line on Boylston Street, killing three people and injuring 264 others, authorities have said. Two brothers were suspected of the attacks. One was killed in a shootout with police. The other was arrested and is awaiting trial.

The 2014 marathon has drawn about 36,000 registered runners, the maximum that organizers allow for the race and 9,000 more than last year. The entrants include more than 1,000 runners from Illinois and hundreds from the Chicago area.

At last year's race, Kilgallon – along with hundreds of other runners – had to stop less than half a mile before the finish line as news about the bombings spread and crowds backed up the road in front of them.

"I just remember standing there in shock," said Kilgallon, who participated in the marathon with a group of friends. "Nobody could really explain what was going on."

Kilgallon said a lot of people were upset they couldn't finish the race, but more than that, they were overwhelmed at not knowing what exactly was going on in front of them.

"We were lucky," said Kilgallon, as she remembered the casualties of that day.

She added that she and her friends planned on spending the next two days visiting Boston's historic sites but instead were "glued to the TV," watching the latest developments on the incident.

"I decided pretty much right away that I was going back," Kilgallon said, adding that she is one of thousands of runners the marathon's organizers allowed to automatic entry this year because they did not get to finish the 2013 race. "It is very important for me to cross that finish line."

Although this year's Chicago winter made it hard to train outdoors to prepare for the race, other runners, like Kilgallon, said are looking forward to participating in the marathon again.

"I don't want my life to be influenced or changed by the lunacy of others," said Northbrook resident Steve Katz, 46, who was in the same group with Kilgallon but was able to cross the finish line.

Katz said he was slowly making his way back to the finish line after taking a shower at his hotel when he found out that something went wrong.

The rest of the day, Katz said, was devoted to figuring out whether anyone in his group had been injured. He was happy to learn no one had been hurt, he said, but it took a long time to finally get in touch with Kilgallon and some of his other friends.

"It was a very emotionally draining experience," Katz said, adding that it was also his first time running in the Boston Marathon.

Katz said some of his family members weren't happy about him going back.

But he said it's important for him to participate this year to thank Boston's people for their support during the last year's tragedy and also to celebrate the city's resilience.

"It's a way to reclaim the race from the terrorists," Katz said, adding that, this year, he's looking forward to sharing a celebration with his friends after they finish the marathon.

Tribune reporter Stephanie Baer contributed.

achachkevitch@tribune.com | Twitter: @chachkevitch