The Grossmünster's twin towers have loomed over Zürich since the 12th century, though not always looking quite so mismatched. The domed caps were added after lightning destroyed the originals in the 1760s and never suited the Romanesque church beneath.

The founding legend is stranger. Charlemagne's horse is said to have knelt where Felix and Regula, Zürich's patron saints, had been beheaded by the Romans. The two picked up their severed heads and walked uphill. Charlemagne built a church where they fell. A replica of his statue watches from the north tower; the original is in the crypt.

It was here that Huldrych Zwingli launched the Swiss Reformation in the early 1500s, dividing Switzerland's cantons into Catholic and Reformed, a split that officially persists today.

VoiceMap's self-guided audio tours trace the Grossmünster's layered past, connecting Roman burial ground, medieval legend and Reformation politics in a single walk through the old town.