Not of the park, but there's a ride that's a tour of their garden.
No there are no bus tours but you do have a tour of the World Showcase, this is a short boat ride within the park. It take you to each side of the lagoon for the World Showcase.
There are no buses inside the park but you can always book a tour of Epcot by either calling ahead or walking into guess relations. Tours do not include admission and also have their own price.
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