Casa Milà draws steady crowds year-round, with the biggest surges in April–October. On busy days, the walk-up ticket line often stretches 30–60 minutes between 10am and 1pm, and can push longer on weekends and holidays. In winter and late afternoons, waits shrink to roughly 15–30 minutes. Lines begin forming before opening, then build again from late morning as tour groups arrive. Entry is through the main doors on Passeig de Gràcia, near the Provença corner; the public queue forms outside and moves to ticket check and security just inside. Book a timed skip-the-line slot and you’ll bypass the box office and head straight to security, which is typically 10–20 minutes.