Day trip from Brussels to Breendonk concentration camp

www.breendonk.be/EN/index.html

You can check schedules at the Belgian Rail site:
www.b-rail.be

All domestic Belgian trains from Brussels stop at all three major central stations: Nord, Centrale, and Midi, so you can use whichever is easiest to reach.

According to the SNCB website, it doesn't appear there's a direct connection. You have to take a train from Brussels to Mechelen, then take a bus from the Mechelen train station to Willebroek, then walk the rest of the way to Breendonk. If you try this without a car, check the map of the bus system at the Mechelen station (every train station has a busmap) to see which bus to take. It is possible that there may be another bus that goes closer to Breendonk (the SNCB website sometimes doesn't automatically direct you to the best bus).

Thanks for the feedback. Tom, you are finding what I was finding...that I could not confirm a clear route and could not gauge the distance we will need to walk. I will try to make sense of the bus routes and see, but I had a heck of a time figuring out all of our itinerary train connections and thought the bus looked even more daunting. Has anyone been to Breendonk?

I haven't been there (even though I spend a few weeks a year in Belgium, I didn't even know it existed!), but it doesn't look to hard to reach without a car. It may seem like multiple connections, but the trip between Brussels and Mechelen, for one, is very quick... assuming you take an IC train and not an IR train. The bus system can seem intimidating because there's no English provided, but it's not hard to figure out. Just look at the route map at the Mechelen station (every major rail station also acts as a bus hub) and find which bus to take. There's usually an automated ticket machine, which does have an English option. If you want to try to interpret Dutch, here's the website for the Flemish bus system (no English):
http://www.delijn.be
Don't try to over-think it before-hand, it's actually not that hard once you get there and you can see everything first-hand.