Budapest HÉV (HÉV means Helyiérdekű Vasút, lit. "Railway of Local Interest") is a system of four commuter rail (Szentendre HÉV, Gödöllő HÉV, Csömör HÉV and Ráckeve HÉV) and rapid transit (Csepel HÉV and Békásmegyer HÉV (part of the Szentendre HÉV)) lines in and around Budapest, Hungary. The HÉV lines were constructed as branch lines of the Hungarian State Railways. The four HÉV lines are operated by the public transport company BKV, yet are not part of the Budapest Metro. The HÉV operates on standard gauge (1435 mm), and is electrified at 1000 V DC. The HÉV lines are planned to become integrated into the metro network.