The main tourist attraction of Mariembourg is a historical steam train that makes a few runs each week to Treignes, passing through some lovely valley country. The town's name derives from Mary of Hungary, as decreed by her brother Emporer Charles V, who had the town built up as a fortress. Immediately next door to Mariembourg lies Phillipeville, named for the son of the same Emporer.
Mariembourg is a borough within the commune of Couvin.