Harvard Bridge Smoot Measurements

Harvard Plaque on the History of the Smoot. Jonathunder (Public Domain)

Two of the world’s most prestigious institutions of higher learning lay claim to this charming bridge that spans the mighty Charles River. Whether you call it the Harvard Bridge, the Mass Ave (or Massachusetts Avenue) Bridge, or the MIT (Massachusetts Institute of Technology) Bridge, one thing is known for sure, its span was calculated using perhaps the most unusual system of measurement ever known, the Smoot.

While pledging to an MIT fraternity, Oliver Smoot dutifully laid down on the bridge one day in 1958, allowing his erstwhile brothers to measure his height (five feet and seven inches at the time). This measurement was categorized as “one smoot.” Members of Lambda Chi Alpha then proceeded across the bridge, marking a total length of 364.4 smoots, give or take an ear.

In recent years, a plaque and colorful smoot markers have been added to the bridge. Google Maps has used the smoot unit in some of its calculations, and MIT’s student-run radio station broadcasts at a wavelength of two smoots.

The Atlas Obscura Podcast is a short, daily celebration of all the world’s strange and wondrous places. Check out this episode about the Harvard Bridge Smoots.

Know Before You Go

Locals not linked to either Harvard or MIT will generally refer to this as "the Mass Ave bridge". It is extremely windy, especially in winter. It is one of three bridges across the Charles River that link Boston proper to Cambridge (the others being the Longfellow Bridge to the east and the Boston University - or "B U" Bridge to the west). "Bridge circuits" (runners'/joggers' routes along Memorial Drive in Cambridge and the Esplanade in Boston) are often defined by the bridges at the east and west ends of the roughly rectangular routes.