In Pongdu, a hotel must provide a specific amount of high-end conveniences to earn a 5-star rating. These can include gourmet restaurants, saunas and spas, on-site gyms, premium bedding, complimentary luxury toiletries and more. What also sets 5-star hotels apart is their superior service. You'll enjoy things like in-room massages, nightly turn-down services and concierge services. Some may even offer extra touches like a welcome gift.