The biggest C in NYC (that I know of)
WikiCU claims that the big C measures 60′ × 60′, with a 12′ stroke width, but according to the proportions of the letter, at least 2 of those numbers have to be wrong: the C is taller than it is wide, and the strokes are much thicker than 1/5 of the height.
WikiCU also states that the big C was originally painted in 1952 by the Columbia University crew team and has been maintained by them ever since.
It was featured in the 2102 documentary film, C-Rock, as well as a July 2010 New York Times article. The rock also appears in The Basketball Diaries, but without the C (it appears to have been painted out digitally).