Boston is one year stronger.
Guarded by extra police officers and monitored by more security cameras, 36,000 runners will step off in the town of Hopkinton on Monday and make their way to the same marathon finish line where two bombs went off within seconds last year.
The anniversary of the bombings was six days ago, and for the city — to say nothing of the runners who lost limbs and the families who lost loved ones — the painful, emotional work of recovery will go on indefinitely.
But the race itself on Monday marks, in a sense, the last 26.2 miles of Boston's comeback.
"Everybody wants to get back out there and show the world that we're still running," said Spencer Aston, who works at Marathon Sports, on Boylston Street, where the first bomb blew out the windows.
The store became a makeshift emergency room in the chaotic early moments after the attach. People ran inside and helped the staff help the injured. They pulled clothes off the rack to treat the dazed wounded.
In the year that followed, business boomed. Non-runners stopped by to show support. Membership in the weekly running club ballooned. The store raised about $700,000 for One Fund Boston, the charity that sprang up after the bombings.
But the most jubilant moment comes Monday, as runners stream across the finish line on a jubilant Boylston Street.
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"Anybody who has run a marathon before, this is going to be the most important one they've ever run in," said Dan Soleau, a Marathon Sports executive who was cheering runners on outside the store on April 15, 2013.
It will also be different. More than 3,500 police officers, double last year, will be along the route. More than 100 cameras have been set up in the Boston stretch alone, and authorities will watch the finish-line crowd from more than 50 "observation points."
Some of the security cameras are more sophisticated than the ones that picked up grainy images of Tamerlan and Dzhokhar Tsarnaev, the brothers accused of detonating the bombs.
Authorities have urged fans not to carry backpacks — both bombs last year were concealed in them — and warned that there will be at least 40 security checkpoints, some with metal detectors. Thirteen miles of steel barricades will line the course.
Security concerns were heightened on the anniversary itself last week, when a man was arrested walking down the street, veiled in black, carrying a backpack with a rice cooker in it. The bombs last year were set off in pressure cookers.
The backpack was destroyed, and police said it had no explosive contents. The man was held on $100,000 bail.
Marathon planners said they will make no effort to rein in the party atmosphere on Boylston Street, a cathartic moment for the city.
"People don't have to worry about anything here," Mayor Martin Walsh told NBC News.
Mindful of the emotion of the day, a city hot line will be staffed for trauma counseling, and in-person counseling will be offered at a church near Copley Square.
The field of 36,000 is about 9,000 more than usual, and includes more than 5,000 runners who were still on the course when the two bombs blew up, killing three people and injuring 264.
Runners who picked up their bib numbers on Sunday seemed supportive of the security measures and not worried about inconvenience.
"I think they have to do whatever they have to do to keep us safe, and this is a small price to pay for being able to run a great marathon," Kathleen Kemp said as she picked up hers.
—By Erin Mccalm of NBC News. The Associated Press contributed to this report.