St Martin’s Cathedral is missing its middle. In 1674 a tornado destroyed most of the nave, and the gap became Domplein, a square nobody planned. The old walls and columns are still traced in its paving.

What survives stands beside the Dom Tower, which rises 112 metres, the highest church tower in the Netherlands. Entry to the cathedral is free. A sculpture above the neighbouring Pandhof cloister shows Martin, a Roman soldier, cutting his cloak in half for a freezing beggar.

VoiceMap’s tour starts on the site of a Roman fortress behind the cathedral, its outline marked by a steel strap in the street. Then it circles the building and walks you into the space the nave left behind.