Explanation
An Agile Release Train (ART) is the primary value delivery construct in the Scaled Agile Framework (SAFe).
It is a long-lived, self-organizing, virtual organization of 5 - 12 Agile Teams that plan, commit, and execute together. ARTs align teams to a shared business and technology mission and deliver solutions in a value stream with common principles and practices. ARTs are cross-functional and have all the capabilities needed to define, build, test, deploy, release, and operate solutions. ARTs operate on a fixed schedule with common iteration start/end dates and duration, and deliver a new system increment every two weeks. ARTs also plan their work at periodic, mostly face-to-face Program Increment (PI) Planning events, and inspect and adapt at the end of every PI. References: Agile Release Train - Scaled Agile Framework, Essential SAFe - Scaled Agile Framework