M4 is a Hungarian expressway (constructed to motorway standards on its final section before reaching the border) which will, upon completion, connect Budapest to Oradea and further Romanian cities.

The route will travel in Hungary through Cegléd, Szolnok, Karcag, Püspökladány, Berettyóújfalu, and Nagykereki before reaching the Romanian border.

Construction contract was awarded to Strabag, with the estimated costs reaching 100 billion Hungarian Forints.

Since the motorway passes through an environmental area, protective fencing was to be installed on the new sections from Üllő towards Törökszentmiklós.

Whilst this section was supposed to open by 2016, construction work was stopped on 30 June 2015, to investigate the companies who were building the road.

In 2018, Hungary received up to 265 million Euros from the EU Cohesion Funds specifically to complete this section of M4.