A city in Japan is having a problem with graffiti. However, it is not the usual type of graffiti with paint from spray cans being used to write on walls. It is graffiti in sand. Officials in the city of Tottori are asking tourists to refrain from writing messages and pictures in the sand of its giant sand dunes. The officials said the graffiti causes damage to the dunes and destroys the pleasure others get in looking at the sand. They said that more than 3,300 cases of 'sand graffiti' have occurred at the tourist hotspot in the last decade. The Mainichi newspaper said there were more than 200 cases reported last year. In January, two overseas tourists were ordered to erase a 25-metre-long message that read: 'Happy Birthday Natalie'.

The Tottori Sand Dunes are famous throughout Japan for their natural beauty. They are the largest and longest sand dunes in the country and form part of a scenic geo-coastal park on the Sea of Japan coast. The biggest dune is 50 metres high. The dunes stretch for 16 kilometres along the coast. The local government wants to improve tourists' understanding of the importance of the dunes. It will set up more signs in English, Chinese and Korean asking people to respect the dunes. More and more tourists are visiting the site each year. A spokesman said: "We are concerned about whether the rules are fully understood, but we want to continue to protect views of the beautiful sand dunes."