Across New York City, bicycles painted white are locked to signposts. Small plaques above the bikes read, "Cyclist Killed Here. Rest in Peace."

This Sunday, groups of cyclists will take memorial rides in all five boroughs to dedicate the newer "ghost bikes," each one honoring one of the 18 cyclists killed in New York City traffic accidents last year.

Around 5p.m. these groups will converge near Queens Plaza, where another bike will be dedicated in honor of the year's unreported or unknown bike fatalities.

The NYC Street Memorial Project, who's organized the annual ride for the past seven years, asks participants to bring flowers or other items to leave at the sites.

“20, 18, 24 deaths might seem like a low number compared to deaths from other sources,” Philipp Rassmann, a volunteer for the group, told DNAinfo. “But those are 20, 18 or 24 individual lives.”

For more details, and a full schedule of Sunday's ride, go here.

In order to sustain their work, the group is raising funds on crowdrise. To donate, go here.

Check out some "ghost bike" photos below, courtesy of NYC Street Memorial Project. For more photos, check out their Flickr page.

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