While in Japan, you absolutely should visit Hiroshima's Miyajima island, but while there, you definitely shouldn't do this.
Lots of sightseeing destinations in Japan come with some sort of qualifier. Akihabara should be on your itinerary if you like anime, for example, and you won't want to miss the town of Hakone if you're interested in onsen hot springs.
Hiroshima Prefecture's Miyajima, though, is absolutely worth visiting, regardless of what specifically drew you to Japan. The mountainous island is covered with centuries-old shrines and lush forests, and wild yet calm deer walk through the town where the ferry port is located. And then there's the sight of Itsukushima Shrine's torii gate rising from the waters of the bay, one of the most iconic views in all of Japan.
When the tide is low, you can actually walk all the way out to the base of the torii, where travelers routinely snap close-up photos of its orange-painted timbers.
But because the lower part of the gate spends much of the day underwater, the wood is cracked and warped in spots. Unfortunately, some tourists have taken to cramming coins into the cracks, creating an unsightly mess that can't be good for the torii.
