The main gateway to the country is La Aurora International Airport, which is located on the edge of the city centre. Public transit in Guatemala City is problematic, and may be frustrating for visitors. A Bus Rapid Transit (BRT), the Transmetro, serves the city. Operating hours are between 4.30am and 10pm during the week, and 4.30am and 9pm over the weekend.Visitors arriving in Guatemala City by bus from other cities will be dropped off at one of the BRT stations on the periphery of the city. These intercity buses have either first or second-class options, with the latter being renowned for being extremely uncomfortable and overcrowded.Both the local and inter-city buses tend to be the popular stomping ground for armed robbers and muggers; visitors are advised to always be aware of their surroundings and to avoid the use of the bus system at after dark.Taxis are available and can easily be hailed at inter-city bus terminals. In other parts of the city it is best to phone ahead and book one in advance. Taxi Amarillo (yellow) cabs are metered and trustworthy.