Looking for books for kiddos 3-6yo

I'm looking for suggestions of books that I can read to my son.

I'd like to skip any fairies, unicorns, witches casting spells etc. because I want to have it set a little bit more in our world, which makes it difficult to find. Harry Potter and Pratchett's Discworld will be his obligatory assignment when he's older.

I'm not for 100% reality, otherwise I'd have to read encyklopedia to him. I'm fine with talking animals etc. I'm looking for adventure books. Doesn't have to be heavily illustrated.

Any suggestions? What were the books that you guys loved as a small kid?