So, what is this bolt?
At the beginning of the 19th century, Manhattan was a mostly undeveloped island, home to around 100,000 residents. But city planners foresaw an influx of nearly 900,000 people, meaning Manhattan needed to be reorganized to accommodate the growing population.
In 1808, a 20-year-old surveyor named John Randall Jr. was commissioned to transform Manhattan into the symmetrical street grid we know today.
Starting in 1811, he spent nearly a decade walking across the island, from 1st Street to 155th Street, marking future intersections with marble monuments. When the ground was too rocky, he hammered iron bolts into it — like this one.
This is the only verified bolt remaining from John Randall Jr.’s project, located at the now-nonexistent intersection of 6th Avenue and 65th Street.
This tiny bolt from 1811 is one of the first markers of the Manhattan that stands today.