To remind the public that a culprit has never been caught, the NYPD parked a cruiser at the spot of the explosion with a large CrimeStoppers poster describing the incident.
It happened just before 11 a.m. in close proximity to the 60th Street and Fifth Avenue entrance. The blast damaged Connor Golden's lower left leg, and his foot had to be amputated.
PHOTOS: Explosion in Central Park
Police and the ATF are also seeking photos and video from anyone who was in the vicinity around the time of July 3, 2016.
The NYPD believes the device was nothing more than a prank or the work of a hobbyist, and investigators said the creator attempted to make a homemade-type explosive and discarded it when it failed to detonate, only to be discovered by the victim.
Golden, of Fairfax, jumped off a rock and apparently landed on the explosive. Police believe it was placed several days earlier.
Golden's dad Kevin Golden spoke with Eyewitness News last year, and he says he's encouraged by what the NYPD is doing. Connor just finished his junior year in college.
No arrests have been made, and local and federal law enforcement are continuing their investigation.
Police also released a new photo showing a plastic bag of crackers that was found at the scene.
It came from one of two bakeries in Union City or Jersey City.
"It has unique markings on it, characteristics to a particular business or bakery, so if folks recognize that bag and have seen it in circulation in the past and know where it would have come from or who had access to that type of bag, we'd like to know about it," said the AFT's Ashan Benedict.
Police are asking anyone with information to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).
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