Main road 4 (Hungary)  The Main road 4 is a west–east direction First class main road across the Alföld region of Hungary, that connects Budapest to the biggest eastern Hungarian cities: Szolnok, Debrecen, Nyíregyháza towards the border of Ukrainian, facilitating access from the capital city of Hungary to the Ukrainian border. The road is long, this is the longest Hungarian main road. Most of the traffic was taken over by the M4 expressway until Püspökladány. The road, as well as all other main roads in Hungary, is managed and maintained by Magyar Közút, state owned company.