90-minute rides, short-term tourist passes are available for periods of 24 hours or 3 days, and longer-term tickets can be bought on the smart ticketing system Lítačka, for periods of one month, three months or one year. Services are run by the Prague Public Transport Company (Dopravní podnik hl. m. Prahy, a. s.) and several other companies. Since 2005 the Regional Organiser of Prague Integrated Transport (ROPID) has franchised operation of ferries on the Vltava river, which are also a part of the public transport system with common fares. Taxi services make pick-ups on the streets or operate from regulated taxi stands. Prague Metro The Metro has three major lines extending throughout the city: A (green), B (yellow) and C (red). A fourth Metro line D is under construction, which will connect the city centre to southern parts of the city (as of 2022, the completion is expected in 2028). The Prague Metro system served 589.2 million passengers in 2012, making it the fifth busiest metro system in Europe and the most-patronised in the world on a per capita basis. The first section of the Prague metro was put into operation in 1974. It was the stretch between stations Kačerov and Florenc on the current line C. The first part of Line A was opened in 1978 (Dejvická – Náměstí Míru), the first part of line B in 1985 (Anděl – Florenc). In April 2015, construction finished to extend the green line A further into the northwest corner of Prague closer to the airport. A new interchange station for the bus in the direction of the airport is the station Nádraží Veleslavín. The final station of the green line is Nemocnice Motol (Motol Hospital), giving people direct public transportation access to the largest medical facility in the Czech Republic and one of the largest in Europe. A railway connection to the airport is planned. In operation there are two kinds of units: "81-71M" which is modernized variant of the Soviet Metrovagonmash 81-71 (completely modernized between 1995 and 2003) and new "Metro M1" trains (since 2000), manufactured by consortium consisting of Siemens, ČKD Praha and ADtranz. The minimum interval between two trains is 90 seconds. The original Soviet vehicles "Ečs" were excluded in 1997, but one vehicle is placed in public transport museum in depot Střešovice. The Náměstí Míru metro station is the deepest station and is equipped with the longest