Dubai Metro is a rapid transit rail network in the city of Dubai, United Arab Emirates. It is currently operated by the French. The Red Line and Green Line are operational, with a major 15 km (9.3 mi) extension to the Red Line known as Route 2020 to the Expo 2020 site announced in April 2015 and opened in 2021. These first two lines run underground in the city centre and on elevated viaducts elsewhere. All trains are fully automated and driverless, and, together with stations, are air conditioned with platform edge doors. Architecture firm Aedas designed the metro's 45 stations, two depots and operational control centers. The Al Ghurair Investment group were the metro's builders.