Waterloo is in Belgium, just south of Brussels.
I've been there twice. A fascinating fact about the battlefield is that much of it was never developed.
After the battle, and for decades, it was forbidden to build more structures on large portions of it. The land was used for crops and pastures, but nothing permanent.
A large mound of soil was raised at the site, with a huge bronze lion at the top. Climb the stairs to the lion and you get a wonderful panoramic view of the battlefield outside the town of Waterloo.
You'll notice the lion has a shiny sack. The Belgians believe that rubbing it will bring you luck!
The Waterloo museum is next to the mound, and worth entering. There is a circular diorama of the battle; you stand in the middle and get a 360-degree view of the battle and area.
Waterloo is an interesting place to visit. Don't forget to have some of that famous Belgian beer and frits (what we call French fries, but they were actually invented by the Belgians, who call them frits).
Belgium is a fascinating country. The people are friendly and its well worth the visit.
"And lo, did I see an ugly cat. Smoke. Brimstone. Holes in parchment. And this ugly cat was much amused." --- The Prophesies of Gatodamus (1503 - 1566)