At least 35,660 runners are set to compete in this year's Boston marathon in the US, as security officials step up security after the deadly bomb attack during last year's event. 

On Monday, more than 3,500 police, and members of 60 different local, state and federal security agencies, will deploy to protect the race.

One million people are expected to show their support for the event and honour the victims and survivors of the attacks that killed three people and wounded more than 260 last year.

Speaking to CBS news network, Massachusetts Governor Deval Patrick vowed that the event would be very safe: "We're very alert. We're very prepared, and we're assuring people as much as we can that it'll be a fun day and a safe one."

But despite the beefed up police presence, "we've tried to strike a balance between enhanced security and preserving the family feel of this day," he said.

One of the alleged perpetrators of last year's attack, Tamerlan Tsarnaev, was killed during a shoot-out with police while his brother, Dzhokhar Tsarnaev, is awaiting trial on 30 federal charges.

The Boston Marathon is one of the six biggest foot races in the world and part of the prestigious World Marathon Majors circuit. It is also the world's oldest annual meet.

'Dear Boston' exhibit

Across the city, people could be seen wearing "Boston Strong" shirts, with banners bearing the mantra proudly displayed in stores, restaurants and hotels.

After the barricades went up near the sites of the bombings last year, so did impromptu memorials. People left flowers, stuffed animals, flags, running shoes, and other items to remember the victims.

Many of those mementos were collected by archivists, and now some of them are displayed in an exhibit called 'Dear Boston: Messages from the Marathon Memorial' at the Boston Public Library, which is just metres from where the bombing took place.

Curator Rainey Tisdale discussed the exhibit with Al Jazeera's Anar Virji.

Source: Al Jazeera and agencies