Last week I noticed that the sunset aligned unusually well with my cross-street, Newton St NW, and it made me wonder if we have any Manhattanhenge-like events in DC. DC can one-up Manhattan — we’ve got a double-henge, if you’ll let me coin a phrase.
The Double-henge
Here in Columbia Heights we have a unique street pattern. Two roads — Park Rd and Monroe St. — come to an apex on 14th St. They go north both to the east and west of 14th St. On a few days a year — centered on May 15 and July 29 — the roads point east toward sunrise and west toward sunset. Click the links to see on suncalc.net. (The alignment isn’t exact, so the effect spans a few days.)
All the henges
Like Manhattan, DC’s grid lines up with sunrise & sunset. It’s on the equinoxes, so we get a boring double-henge on those days too.
Some of the state avenues are kind of close to the solar azimuths on the solstices, but the peak days are a few days off. In the summer it is on the same days as the Columbia Heights Doublehenge. On those days the avenues parallel to New York Avenue line up with sunrise and the avenues parallel to Pennsylvania Avenue line up with sunset. Around the winter solstice — Nov 5 and Feb 6 — the avenues parallel to Pennsylvania Avenue line up with sunrise and the avenues parallel to New York Avenue line up with sunset.
I wondered for each day of the year, what was the DC road that best aligns with sunrise and sunset. If you’re driving these would also be the roads to avoid (h/t @knowtheory). Here’s a table for the next year. The links will show you where exactly it is:
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