Question: Bern is a canton of what 26-member group?
Sentence (from "Cantons of Switzerland"): Two further major steps in the development of the Swiss cantonal system are referred to by the terms "Acht Alten Orte" ("confederation of eight"; between 1353 and 1481) and "Dreizehn Alten Orte" ("Thirteen-Canton Confederation", during 1513–1798); they were important intermediate periods of the Ancient Swiss Confederacy.
Relevant evidence: No