Palazzo Grimani (1560s) was built by Giovanni Grimani to display his collection of Greek and Roman antiquities. The Tribuna — a double-height octagonal room with marble walls, stucco ceiling, and niches for statues — was designed as a miniature Pantheon INSIDE a palace. Mannerist frescoes by Giovanni da Udine and Francesco Salviati (grotesques, mythological scenes) were recently restored and glow with original color. €10. Santa Maria Formosa area. Almost nobody visits. The most spectacular Renaissance interior in Venice after the Doge's Palace.
Highlights: Tribuna (octagonal, double-height, the spatial climax). Sala del Camino (fireplace room, Mannerist frescoes). Sala a Fogliami (leaf room, Giovanni da Udine grotesques — the same artist who painted the Vatican Logge with Raphael). Practical: Ramo Grimani, Castello (near Campo Santa Maria Formosa). €10. Open Tue-Sun 10am-7pm. 45 min. Combine: Grimani → Santa Maria Formosa (Bellini altarpiece, 2 min) → San Rocco Tintoretto (15 min walk).