Favignana is butterfly-shaped, 8km wide, and entirely bikeable in 3 hours. The largest of the Egadi Islands (off western Sicily), it was once the Mediterranean's tuna-fishing capital — the mattanza (ritual tuna slaughter) defined Favignan identity for centuries. Today: the tuna factory is a museum, the quarries where they cut tufa stone are now swimming pools filled with turquoise sea, and the entire island operates at a pace where the most stressful decision is which cove to swim in next. 30 min ferry from Trapani. Day trip works. Overnight is heaven. Italian islands guide →
Cala Rossa — the star. An abandoned tufa quarry flooded by the sea — you swim inside geometric carved walls of golden stone, the water so clear you see the bottom at 8 meters. The most unusual swimming spot in Italy. Access: 15 min bike from town + 10 min walk down. Cala Azzurra — sandy bottom, shallow, turquoise, family-friendly. The "easy" beach. Bue Marino — sea caves (named for the monk seals that once lived here). Lido Burrone — the longest sandy beach, stabilimenti available (€15-20).
Stabilimento Florio (€8) — the massive tuna factory (1859) that processed the entire Mediterranean tuna catch. Now a museum of industrial archaeology + marine biology. The most beautiful factory building in Italy. Bike the island: Rent at the port (€8-12/day). The island is FLAT (mostly) — circuit all major coves in 3h with swimming stops. Sunset at Punta Sottile (western lighthouse — Africa visible on clear days).
Ferry from Trapani: Liberty Lines hydrofoil (30 min, €12-15) or Siremar (1h, €8). Multiple daily departures. Day trip from Trapani works (ferry 8:30am → return 6pm). Hotels: €60-150 in Favignana town. Combine: San Vito Lo Capo + Trapani + Favignana + Erice = the ultimate western Sicily week.