Manhole covers that left their mark on the city

"Looking up at New York’s buildings isn’t the only way to get a sense of the city’s past. Cast your eyes down on the sidewalk and street, and you’ll start seeing an incredible variety of manhole covers—many from the 19th and early 20th centuries. These iron lids serve a utilitarian purpose. But the men who made them at Ironworks across the city imbued them with a sense of pride and craftsmanship. Jacob Mark created his signature covers with colored glass, which look like glistening jewels. The one at top of the page was discovered in Tribeca. ..."
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