The Opera Royal season is on the Opéra Royal de Wallonie website. La Monnaie theatre, in the historical center of Brussels, near the City Hall and the Grand Place, displays also musical and performance program on its website. 15 minutes before the beginning of the performance, remaining seats are sold to a discount price of 8€ for youths (-28), pensioners (+ 65) and unemployed.
You will find the agenda of most of the theatres on the website iDéarts. The website Agenda shows also a full overview of leasures amd cultural life in Wallonie : cinemas, theatres, concerts, activities for children, boot sales...
In order to know more about monuments and sites of Brussels-Capital region, you can visit the website of la Direction des Monuments et sites of the minister of Brussels-Region. This administration is in charge of protecting, conserving and restauring sites, trees, parks and gardens of Belgium.
Brussels has got numerous museums and sites to visit (with the famous Atomium, built in 1958 for the Universal Exhibition, as was the Eiffel Tower built at the end of the XIXe in Paris). We can list (amongst severals):