Since we're already in Luxembourg, and there's a direct fast train to Brussels - peeing boy fountain place was also checked.
Manneken Pis - that's actually the name of this very small bronze fountain sculpture in Brussels.
However that's not the main point of visit, there are few other items worth seeing in this city.
The central square has a lot of nice old buildings, with a lot of different sculptures, statues an so on.
Brussels is not only old buildings, it's also a place where you can find a huge number of different brands of beer, chocolates and other tasty items.
Apart from that - there's the Atomium and "Mini Europe".