It was a scheme intended to provide benefits to both our health and environment and has proved hugely popular.

More than 50,000 people have registered to use the nextbikes scheme across Cardiff - hailed as the company's most successful in the UK.

But an increasing number of the 500 bikes currently in service are being abandoned or vandalised, resulting in fewer available at any one time.

"It's destroying the scheme for other people," said user Jac Cooper.

Nextbikes are soon to double the number of bikes available but say they have also had to introduce "higher and steeper" fines for bad behaviour.