How do we know what is in the bible is true?

I am a firm believer in God. I know within my being that something created me and every thing around me. But what I want to know is how can we be so sure that what we read in the Bible is true? It was written by man. Back in a time when they really didn't know anything. I am sure there was a lot of superstition that we have overcome over the years. But yet everyone continues to believe everything that is in the bible. I have total faith in God. I just don't know what to believe otherwise. There are so many contradictions in the bible compared to real life now. In the Sodom and Gomorrah story it said that God cursed them and destroyed the cities with fire and brimstone. Well on discovery channel they found that it was a meteor shower and the rocky atmosphere in the area confirms that it was a meteor shower but yet people put all they're faith in a book written by early man. Where are all of the miracles? Where are the angels? I don't know. I was raised going to church and reading the bible and it just doesn't make any sense to me at all. The God thing makes sense because something, a spirit, a being, a feeling or something created all we know of life but I don't understand the concept of believing the word a man who lived so long ago. There was a story about the people trying to build a tower to heaven and God struck them down and created the nations. Different languages, skin colors etc., and now we are able to surf outer space and we are learning to speak several different languages. We haven't been struck out of the sky. There are so many stories that just don't make sense. Why put our faith in a book that is filled with lies from people of long ago? I know that there was a flood but I don't think it happened the way it states in the bible. I am sure that the bible is good for one thing. Its a guide for the living. The way that we should treat each other and the way we should live. But there is just too much faith in stories that may have never happened. We don't have any proof that many of the stories are true. They are the thoughts of a superstitious group of people. How do we know what really happened in the beginning was real or true?