Charles River Esplanade Pi Plaque

The Charles River Esplanade in Boston is lined with benches accompanied by small plaques featuring inspirational words, quotes, and personal messages to friends and loved ones. Among them, there is one plaque with no words at all. Instead, a set of never ending numbers sit in neatly spaced rows.

The first 100-plus digits of the mathematical constant, pi (π), are dotted across the plaque. The number itself has become somewhat of a celebrity, recognized by the international holiday, Pi Day, every March 14, and a system of mnemonic techniques for memorizing as many digits of pi as possible (Piphilology), and now, a plaque. 

The Esplanade offers a program where donors can sponsor a bench for $5,000, complete with a 4x6-inch personalized bronze plaque. Almost all of these plaques have the name of the donor or gifting family, but the pi plaque lacks any identifying information about who the generous donor might be. Perhaps it was sponsored by someone who greatly enjoys pi, or perhaps it was commissioned by the Massachusetts Institute of Technology, which sits directly across the Charles River.

If you're a fan of the number pi, then the plaque may be worth a visit, perhaps, with a slice of pie.