You don't have to be a great fan of antique cars to appreciate this museum. In fact, unless you actually hate cars, this is a really fun and impressive place. Auto World is comprised of the personal collection of only one man, accumulated over decades. It not only includes gigantic old touring cars, like Rolls Royce, Bentley, and the even more luxurious Hispano-Suiza (the favorite of many old Hollywood silent screen stars). AutoWorld also includes such oddities as the tiny post-war Messerschmidt economy car, which looks like a tiny submarine, and the American Amphicar (the 1950s amphibious car which can be driven into water and converts into a boat, and then driven back on shore). I can't even remember all of the other odd European models, dating back to before World War I. There is also a small section devoted to pre-auto carriages.
Auto World is in a gigantic museum complex in the Brussels suburbs, called Parc du Cinquantenaire. Other attractions there include art and military museums, and a couple of nice little cafes. There is a Metro stop at each side of the park, so it is convenient to visit.