IIRC, we were only required to learn about our Alpha chapter at Barnard, and of course our own chapter designation once we had one. Most of my chapter sisters knew which other schools in the Boston area had chapters (but not necessarily their designations).
Off the top of my head, I can remember the following single-letter chapters:
Alpha - Barnard (founding chapter)
Gamma - Columbia Teachers' College
Delta - Adelphi (longest continuously operating chapter)
Epsilon - Sophie Newcomb College / Tulane University (first chapter outside New York State)
(Beta Chapter was at Hunter College, but I had to cheat and look that up on the AEPhi web site
)