Google has launched its transit service in Ireland, for the first time allowing Irish users of its maps to get directions using public transport .

The entire public transport system has been mapped helping people to plan trips across any part of the State.

The Google Transit service is part of Google Maps and is already encompasses over a million transit stops in hundreds of cities. It links up map service directions with public transport routes and times.

The free service is a collaboration between Google and the National Transport Authority.

The authority provided the technology company with the route network and data behind its journey planner.

The service incorporates Dublin Bus, Luas, Bus Éireann and Irish Rail, as well as all commercial bus operators.

"Hello Ireland! Easily plan trips anywhere in the Emerald Isle w/ Google Maps transit," Google said in a tweet today. The service allows users to specify their departure or arrival time, choose from several trip options, find the departure times of the next bus or train and the walking directions to the nearest stop.

"Commuters and travellers across the Republic of Ireland are now able to use Google Maps on the web, on their Android phones, iPhones or tablets to plan their public transport journeys," said Minister for Public Transport Alan Kelly as he launched the service. " It's all about making it easier for commuters and visitors to use public transport," he said.

Google Transit is already available in over 800 cities and Google Maps has over a billion active monthly users, half of whom are on mobile devices. It “is great to add the towns and cities in the Republic of Ireland to this ever-growing list”, David Tattersall product manager at Google Maps said today.

Google says its transit service “is a public transportation planning tool that combines the latest agency data with the power of Google Maps”. The service “integrates transit stop, route, schedule, and fare information to make trip planning quick and easy for everyone”, it says.

Transit can be accessed from google.ie/transit