There are several theories about Pest. One states that the name derives from Roman times, since there was a local fortress (Contra-Aquincum) called by Ptolemy "Pession" ("Πέσσιον", iii.7.§ 2). Another has it that Pest originates in the Slavic word for cave, ''пещера'', or ''peštera''. A third cites ''пещ'', or ''pešt'', referencing a cave where fires burned or a limekiln.