Last week marked one of the quirkiest events on the Boston calendar: MIThenge, the twice-a-year occasion when the sunset shoots straight through the door at the end of MIT’s Infinite Corridor. On these afternoons, the long hallway that links the university’s buildings aligns with the sun the way Stonehenge (putatively) aligns with the solstices.
The equivalent phenomenon in New York is known as Manhattanhenge, when the setting sun lines up with Manhattan cross streets and slices dramatically between the city’s towers. It occurs twice a year, once in late May and again in mid-July. (Really four times if you count the rising sun, which is apparently too early for anyone to be in the mood to talk about.)
Here in Boston, like most everywhere else in the country outside New York, we don’t have the skyscraper street canyons that make Manhattanhenge remarkable. But perhaps our lack of any overall street system makes up for it; Manhattan gets only a couple of “henge” days each year, while in Boston the sun rises and sets straight over different streets on any number of dates.
Despite the apparent chaos of Boston’s street network, some individual neighborhoods—South Boston, East Boston, and the Back Bay, for example—have relatively orderly street grids. Because of the unique geography and history of each neighborhood, the grids are all set at different angles, giving each neighborhood its own “henge.” And although our straight streets don’t tend to be very long, some thoroughfares, like those in Cambridge, do cut direct paths that provide an uninterrupted view of the sun across multiple neighborhoods. (They also send the sun straight into the eyes of drivers, so “henge” dates are a time for pedestrians to be extra cautious.)
If you look at a calendar of the sun’s positions through the year, and match the azimuths of sunrises and sunsets—their angles relative to north—to the angles of reasonably long straight streets, you can come up with a rough chart of neighborhood “henges.” Here’s a map of a few of those that should—weather permitting, and with some room for error—offer dramatic long views of the sunrise or sunset.Andrew Woodruff is a Cambridge-based cartographer for Axis Maps, and coauthor of the Bostonography blog.