פירוש על ברכות 66:12

I.e. note it well.

After the destruction of the Seminary of Nehardea in 259, that of Pombedita sprang into prominence and the town received the name of "Capital of the Exile" (Rosh. Hash. 23b). It is situated 22 parasangs North of Sura in Babylon, at the mouth [poma] of the canal Bedita. Neubauer, p. 349.