What's the must-see thing in Florence?

Brunelleschi's Dome is the thing in Florence you'll remember 10 years from now. The cathedral itself, started in 1296, sits free to enter on Piazza del Duomo, and the interior is cooler than you'd expect, all dim stone and incense. For the dome, you book a timed slot (the €30 combined Opera del Duomo pass covers the Baptistery and Giotto's Bell Tower too), climb 463 steps through a narrow passage between the inner and outer shells, and emerge at 91 metres with Vasari and Zuccari's Last Judgment fresco close enough to see individual brushstrokes on its 3,600 square metres of painted surface. The stairwell narrows to about 60 centimetres in places. You'll feel the rough stone walls against your shoulders and hear your own breathing echo off 600-year-old brick. Book at least 3 days ahead in summer; same-day slots on the official duomo.firenze.it site tend to sell out by 9am.

The Uffizi, founded in 1560 as Cosimo I's administrative offices, is the second priority. Mind you, second still means essential. Botticelli's Birth of Venus and Primavera hang in rooms 10-14 on the upper floor, and the warm amber light through the Arno-facing windows in late afternoon makes the colours look nothing like the reproductions you've seen. The Uffizi itself smells like old wood and floor polish. Timed-entry tickets run €20-25 depending on season, and the line without one can reach 3 hours on a June morning. Book through the official uffizi.it site, not resellers. Tuesday is the quietest weekday. The museum closes Mondays. Plan 2.5 to 3 hours inside; the corridor layout means you walk about 2 kilometres total, so wear shoes you'd walk in, not stand in.

Ponte Vecchio dates to 1345 in its current stone form, rebuilt after a flood in 1333 swept away the earlier wooden crossing. Butchers and tanners held the shops originally, but Grand Duke Ferdinando I replaced them with goldsmiths in 1593 because the smell offended him on his walk through the Vasari Corridor overhead. That enclosed passageway, built by Giorgio Vasari in 1565, still runs along the bridge's upper level connecting Palazzo Pitti to the Uffizi. The shops themselves are tiny, most about 3 metres wide, with wooden shutters that fold down into display cases each morning around 9:30. The bridge survived WWII while every other Arno crossing was dynamited in August 1944. It's shoulder-to-shoulder by 10am, but the sunset view, when the Arno turns copper and the shopfronts glow warm yellow, is worth the crowd. Walk south afterward into the Oltrarno. The neighbourhood between Palazzo Pitti and Piazza Santo Spirito still has more resident Florentines than tourists on most evenings. Trattoria Cambi on Via Sant'Onofrio does bistecca alla fiorentina for around €45-50 per kilo, dry-aged Chianina beef charred over oak coals, pink and warm at the centre. Woodsmoke from the kitchen drifts down Via Sant'Onofrio after 7pm.

The Baptistery's restored ceiling mosaics, dating from the 1220s, are likely the most underrated thing on Piazza del Duomo, and your combined Duomo pass includes them. Santa Croce (founded 1294), where Michelangelo, Galileo, and Machiavelli are buried, tends to run €8 admission and rarely has a queue. The Accademia, home to the original David, needs advance booking and costs €16, but the 5.17-metre marble figure is frankly better experienced as a 20-minute visit than the 2-hour ordeal the crowds make it. If you have 3 days, the Duomo climb goes on day 1 because it orients you to the city from above. The Uffizi fills day 2. The Oltrarno walk plus Ponte Vecchio at sunset fills day 3.