How Big Is a Manhattan-Sized Iceberg?

Yesterday, while everyone else was oohing and aahing over a newly calved iceberg twice the size of Manhattan and pondering its significance in terms of climate change and sea level rise, I was stuck on the "Manhattan" part. Couldn't we come up with some better size comparison? Call me a country-bumpkin, but I certainly don't have an intuitive sense of how big Manhattan is. Grist's Chris Mims seemed to read my mind and broadcast it on Twitter.

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Chris may have been kidding, but I wasn't. What ensued was a brief conversation about the impossibility of finding a universally recognizable size comparison, and the need for better storytelling in science journalism. You can read it all on Storify.
But I'm curious: do you know how big Manhattan is?