Ubud is located in the middle of Bali, and if you're planning on getting there via flight, you really need to go to the Denpasar Bali Airport, which is located on the southern tip of the island. From there you can either rent a car or take a bus to get to Ubud. The island isn't necessarily huge, but it can take a while to get there because of the terrain, and not all of the roads are paved very well. Also, every year the roads get damaged due to the rains and harsh weather, so this can also slow things up a bit.
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