Oldest University in the US (1636)
Harvard University

Oldest Foreign Bookstore in the US (1856)
Schoenhof's

Oldest Sporting Goods Store in the US (1867)
Brine's (in Belmont since 2004)

Oldest College Cooperative in the US (1882)
The Harvard Coop

Oldest Barber Shop in Massachusetts (1898)
LaFlamme

Oldest Poetry Bookstore in the US (1927)
Grolier

First soft-serve frozen yogurt (1972)
The Spa

Chains originating in Harvard Square
Crabtree & Evelyn, Joan & David shoes, The House of Blues, Jasmine/Sola, Origins, Cross