While you may not need a physical passport to enjoy the slides at Siam Park Tenerife, you are strictly required to show a valid photo ID that matches the name on your e-ticket for entry. In 2026, a passport is the most universally accepted and recommended form of identification for international tourists. This requirement is particularly important if you have purchased a "Twin Ticket" (combined with Loro Parque) or if you are using a discounted resident ticket, as staff frequently verify identity at the turnstiles. Additionally, if you plan to rent a locker, use a credit card, or check in for a private cabana or villa, having your ID is essential. While you can keep your original passport in a secure park locker, having a digital photo of it on your phone is a good backup; however, for the initial gate entry, most park policies specify that a physical government-issued document (passport or national ID card) is necessary to validate your admission.