Carfax Tower stands at the precise centre of Oxford, where four Roman roads once met. The name comes from the Latin quadrifurcus, meaning four-forked, via the French carrefour, and the crossroads it marks has been the city's beating heart since 1122.

The tower is all that survives of St Martin's Church, Oxford's official town church, demolished twice and rebuilt twice before the Victorians finally lost patience and pulled it down entirely to ease the traffic. The tower, stubborn as ever, stayed.

Look up, and you'll see the Quarter Boys, two small figures that strike a bell every fifteen minutes. The originals are now in the Museum of Oxford. No building in central Oxford may rise higher than the tower's 74 feet, a rule that has held for centuries, though recently bent.

VoiceMap's self-guided audio tours use Carfax Tower to anchor Oxford's most dramatic conflict: the St Scholastica Day Riot of 1355, in which a tavern argument over bad wine escalated into three days of bloodshed that killed 93 people, and the repercussions of which echoed for five centuries.