Offerings are a problem for Itsukushima Shrine, a popular tourist spot in Hatsukaichi, Hiroshima Prefecture, designated as a UNESCO World Heritage site. Instead of throwing coins into an offertory box, visitors push them into cracks in its torii, causing damage.

Located off the coast of Itsukushima Island, the red gate of the shrine appears to float at high tide, and is approachable by foot during low tide.

During low tide, a number of tarnished ¥10 and ¥5 coins are seen scattered around the pillars of the gate along with barnacles.

Shrine staff say that inserting coins into the cracks of the pillars damages the gate, and tourists are asked not to do so.

The gate, which is exposed to wind and flooding, has been reconstructed seven times, most recently in 1875. The shrine is considering doing repair work on the deteriorated gate, since an inspection in September revealed a hollow space inside the main pillar.

The shrine has failed so far to find an effective way to prevent visitors from putting coins in the cracks.

An official at the tourist association in Hatsukaichi said it is unknown when the custom of putting coins in the cracks began. But a man who lives in the neighborhood said he has seen it done for the past 20 years or more.

A 68-year-old woman from Koriyama, Fukushima Prefecture, who came to the shrine on a sightseeing trip with her sister earlier this month, said she was so excited to see the gate so close that she inserted a coin in a pillar. "I didn't know that it was a bad thing to do," she said.