The best view of Florence costs you a hill, and this is the hill. Piazzale Michelangelo is the postcard — but the walk is really about what sits above it, where the coaches don't go.
About three kilometres, best in the morning before the terrace fills. Start at Porta San Niccolò by the river and take the Rampe del Poggi, the looping garden ramps rather than the brute stairs; the city unfolds in stages as you climb. At the top, Piazzale Michelangelo gives you the lot at once: duomo, tower, bridges, hills. Take it in, then keep going up.
Past the plain San Salvatore al Monte — Michelangelo's bella villanella, his "pretty country girl" — the slope ends at San Miniato al Monte, a Romanesque church with a marble floor of zodiac beasts and monks who still sing the chant. This is the calm the view doesn't have.
Behind it, the cemetery holds the man who wrote Pinocchio. Walk back to the piazzale and take the Bus 12 down.