Atomium is one of the best places in brussels to be. You can take the metro from Rogier to Heysel to reach atomium. The ticket is not very expansive and you can buy online as well.
The place is usually crowded especially on weekend. Some Glimpse of Atomium. From the top floor, you can take a panoramic view of the city. Other floor are for exhibitions.
I’m sure you’ve already added your great photos and informative review on Google Maps. Feel free to share a photo from the top here as well! I’m curious to see the view.