Siena Cathedral (Duomo di Siena)

Siena Cathedral stands as Italy's most striking example of black and white striped marble architecture, built over two centuries starting in the 1200s. The real treasure lies beneath your feet: 56 intricate marble floor panels telling biblical stories, created by 40 different artists over 200 years. You'll also find Pinturicchio's vibrant frescoes in the Piccolomini Library that look like they were painted yesterday, not 500 years ago. The unfinished Facciatone offers panoramic views across Siena's terracotta rooftops.

Walking into the cathedral feels like entering a zebra-striped jewel box where every surface tells a story. The marble floors are usually covered by protective boarding, but when exposed (late August to October), they transform the space into a walkable art gallery. The Piccolomini Library glows with Renaissance colors, while climbing the Facciatone gives you breathing space and sweeping views after the intensity inside. Audio guides help decode the complex iconography.

Skip the basic EUR 5 cathedral-only ticket and get the OPA SI Pass for EUR 13 (EUR 15 during floor season). Most visitors rush through without realizing the crypt and baptistery are equally impressive. The library is small but spectacular, don't miss it. If you're here during floor season, arrive early as crowds build quickly. The Facciatone climb is easier than Torre del Mangia with better views.