Bradford has been named top of the list of the 20 greenest cities in Britain, an environmental survey has revealed.

The city has shed its "dark satanic mills" image as a powerhouse of the industrial revolution and now boasts wildlife such as otters and kingfishers within walking distance of the once-filthy city centre, the survey has acknowledged.

It has comes top of the environmental impact league table in the sustainable cities index, published by a charity founded by environmental campaigner, Jonathan Porritt.

Data collated by the Forum for the Future indicated that Bradford is best in air and river water quality, waste collected per head and its "ecological footprint" - the impact of services, housing and travel on the environment.

But, despite the city's success in the green league table, it fared less well on quality of life and so-called "future-proofing" indicators that show the progress the city is making towards sustainability.

It was listed ninth overall of the 20 cities included in the study.

Brighton and Hove came top of the list overall with Liverpool, next year's European Capital of Culture, being named the worst.