There are too many plastic bottles sitting in landfill, littering streets and polluting our oceans. Italy is a particular culprit: the country, from Rome to the countryside, has the highest per capita use of bottled water in Europe, at a massive 188 litres per person per year.

At the same time, there’s an ecological necessity to switch away from cars and use public transport.

The mayor of Rome, Virginia Raggi, has found a way to hit two birds with one stone.

The capital city has introduced machines in three major metro stations that convert plastic bottles into €0.05 of travel credit. Passengers at Cipro on the A-line, Piramide on the B-line, and S.Giovanni on the C-line, would need to insert 30 bottles to pay for a regular €1.50 journey.

The 12-month ‘Ricivli + Viaggi’ programme (Recycle + Travel) aims to reduce waste build up in the city, and prevent people from travelling without a ticket.

La campagna +Ricicli+Viaggi è un successo: ben 100mila le bottiglie riciclate nelle metro di Roma in poco più di un mese. Numeri che ci raccontano una formula vincente ed un’attenzione crescente nei confronti della sostenibilità ambientale: https://t.co/QnmKk24glG pic.twitter.com/B9JbVe67dN

— Virginia Raggi (@virginiaraggi) August 28, 2019

It comes after Mayor Raggi promised a ban on single-use plastics in March.

Rome will review the programme once it is over to assess whether it should expand. In the first month, Raggi says that so far, 100,000 bottles have been recycled.

The programme is similar to initiatives in Istanbul, where passengers could add credit to their MetroCards by recycling aluminium; and Leeds, UK, where drivers could pay at car parks with plastic bottles.