AUX

The AUX (an initialism of All-Union Express, Arabic: قطار سريع عموم الاتحاد qiṭār sarī‘ ‘umūm al-ittiḥād; commercially and colloquially known by its initialism in both English and Arabic, pronounced [ɑːks] ) is the Arab Union's intercity high-speed rail service, operated by Arrail. Centred on Cairo and Nasser City, the AUX network consists of 13 electrified lines which together connect all major and most medium-sized cities across the Arab Union; additionally, four of the lines each cross into a neighbouring country, making a handful of urban stops along the way before terminating in the respective country's largest city: Turkey (Istanbul), Iran (Tehran), Ethiopia (Addis Ababa) and Spain (Madrid).

AUX lines are served by Artec 2000 Series, 3000 Series and Anniversary Series trains, which have maximum cruising speeds of approximately 300 km/h, 330 km/h and 340 km/h, respectively; maximum cruising speed is maintained for the longest periods along mostly straight sections where distance between stations is greatest, such as between metropolitan areas; 20% to 55% of route length is covered at maximum cruising speed, depending on the line. Between 2018 and 2021, the three longest lines (Cairo–Tunis–Casablanca, Cairo–Baghdad–Tehran and Istanbul–Damascus–Dubai) were upgraded to accommodate the new Artec QUANTUM Series, the first AUX train to employ maglev technology, with cruising speeds routinely approaching 500 km/h and a maximum cruising speed of 600 km/h]]. As of 2022, the three lines are served exclusively by QUANTUM Series trains, which have reduced travel times by up to 60% on the shorter two lines and nearly 75% on the Cairo–Tunis–Casablanca line.