National Basilica of the Sacred Heart

One of world's largest churches
Word to the wise: The best way to get to the church is to take the metro to Simonis and walk through the charming Parc Elisabeth.

As the fifth largest church in the world and the largest Art Deco building in existence, the National Basilica of the Sacred Heart in Koekelberg is a breathtaking experience for all visitors.
Perched on Koekelberg Hill, the enormous church dominates the Brussels skyline, an under its green copper dome, which rises 89 metres into the sky, a 360 degree outdoor gallery offers spectacular panoramic views of the city. The church itself is a Unesco World Heritage Site, built over 50 years and two world wars, and features notable modern stained-glass windows.

There is a lot to see inside, so take your time to wander around its two museums, exhibitions, and numerous sculptures. And don't forget to take the elevator up to the gallery for a view that is simply awe-inspiring.