The humble manhole cover might not seem like much of a blank canvas, but one Japanese city is reimagining the possibilities with illuminated versions featuring anime characters.

Tokorozawa, near Tokyo, is hoping the unusual additions will attract visitors, including enthusiasts of the painted decorated manhole covers that adorn some of Japan's streets.

"They're Japan's first illuminated manhole covers," city official Junichi Koike told AFP.

Japan is no stranger to decorative manhole covers, boasting everything from ornately engraved versions to ones painted with city mascots.

Cities have been sprucing them up for at least four decades, with the goal of improving the image of the sewerage system.

A subculture of manhole cover fans has sprung up, with enthusiasts swapping information on social media about their favourite versions under the hashtag #manhotalk.

"'Manholers' enjoy discovering different kinds of manhole covers," Koike said.

"We hope the new illuminated ones will further improve the dirty and smelly image of manholes and also revitalise the local economy by bringing in visitors."

A total of 28 manhole covers were installed throughout the city on August 1, featuring anime characters like Gundam robot and from "Neon Genesis Evangelion" sci-fi animation series and "The Melancholy of Haruhi Suzumiya" TV series.

The covers light up from 6 pm to 2 am using solar power, illuminating the pavements that lead from the city's main train station to a new cultural complex, featuring an anime museum.

They are part of the project in which the city collects revenue by allowing private companies -- in this case major media group Kadokawa -- to use manhole covers for advertising. 

But while city officials say the extra street lighting could serve as a crime deterrent, security guards are having to expand their patrols to pass by the covers in case anyone tries to steal or damage them.

The covers have had a positive reception so far, from enthusiasts and local residents alike.

"They are more illuminated than I expected," manhole fan Kaoru Morita, 55, told AFP.

"Usually when you are looking for manholes, they are actually not so easy to spot. But I can see where these are from far away, so it's helpful for a person like me looking for them."

Tatsuhiko Sato, 29, who lives in the city, admits he was a bit surprised to see the covers at first.

"But it was a good surprise. The animations I always watch can also be enjoyed in this way. It's also fun for children."

There are some 15 million manholes in Japan, but only a fraction feature painted designs, which boost the cost of a cover from around $600 to sometimes double that.

The cost of the illuminated covers has not been disclosed, but is covered by the sponsor, and the funky feature will stay in place for as long as the firm continues to pay for it.