There is an increased police presence around the area, one week after the deadly blasts rocked one of America's busiest cities. NYPD Commissioner Ray Kelly says the stepped-up patrols aren't going away anytime soon.
Local officials say they're not taking any chances because of New York City's high profile targets like Times Square.
Before Monday, police and the FBI have thwarted every single terror attack over the last 12 years, or the terrorists have badly bungled their plots like the alleged Times Square car bombing.
But as Boston proved Monday, dangerous individuals are still out there.
"We haven't really been free of it," former New York City Mayor Rudy Giuliani said. "This has been going on interrupted for 12 years. This happens to be one that got through the cracks unfortunately."
Police have beefed up patrols at hotels, landmarks, the Financial District and Times Square.
"Anywhere we've gone, there's been security everywhere," tourist Celeste Inocencio said. "We are still a little worried about back home."
For a lot of New Yorkers, the events remind us of the days right after 9/11. Lamwakers have argued for years that big cities need more anti-terrorism money, and that funding can't be cut. They say this week proves their point.
"For those who think somehow this war is over, who think we can afford to relax, cut back, the answer is no we cannot," New York Rep. Peter King said. "There are people out there who want to kill us. They will not stop. We have to stop them."
On Sunday, thousands of New Yorkers donned "I Run for Boston" bibs during a 4-mile run Sunday in Central Park, one of a number of races held around the world in support of the victims of the marathon bombings.
"It was really quite a powerful morning," said Mary Wittenberg, CEO of the New York Road Runners.
Wittenberg said later Sunday at another run dedicated to victims that she had been in close communication with Boston Marathon organizers.
"This is one community," Wittenberg said. "After 9/11, we were all New Yorkers. After last Monday, we're all Bostonians. And I just want to add, I think now we've got one world of runners."
More than 6,000 runners took part in Sunday's City Parks Foundation Run for the Parks, which was planned before Monday's bombings.
Organizers turned it into a show of solidarity by selling "I Run for Boston" T-shirts with proceeds going to the One Fund Boston, the official fund for those affected by the bombing.
Other "Run for Boston" events have taken place around the U.S. and the world, with many runners wearing blue and yellow, the official Boston Marathon colors.
(The Associated Press contributed to this article)