Given a list of cities and the euclidean distances between each pair of cities, what is the shortest possible route that visits each city exactly once and returns to the origin city?

TravellingSalesman[cities]

[url=https://en.wikipedia.org/wiki/Travelling_salesman_problem]Travelling salesman[/url] is an [url=https://en.wikipedia.org/wiki/NP-hard]NP-hard[/url] problem in [url=https://en.wikipedia.org/wiki/Combinatorial_optimization]combinatorial optimization[/url], important in [url=https://en.wikipedia.org/wiki/Operations_research]operations research[/url] and [url=https://en.wikipedia.org/wiki/Theoretical_computer_science]theoretical computer science[/url].