Unless you’re staying at an expensive 5-star hotel, which tend to be more accommodating with early arrivals, beware that most accommodations are strict about their check in times. Most 4-star or less properties are completely inflexible when it comes to arriving early, so don’t expect to turn up at the front desk hours before and be shown to your room. They will however happily stow your luggage and ask you to return at the published check in time to complete the check in process. If you are going to arrive several hours before check in time, I’d recommend packing your valuables and anything else you need in a day bag so that you can go exploring until you’ll be allowed into your room.
Tips for your first trip to Tokyo
