Mons.Arena  Mons.Arena is a multi-purpose indoor arena in Mons (Jemappes), Belgium. Mons.Arena has a capacity of 3,700 people. It hosts the home games of Belfius Mons-Hainaut basketball club. In March 2019, the name was changed to Diamonte Mons.Arena until 31 December 2020 because of sponsorship agreements.