My first was I think about 2 1/2 hours or something like that, but I was induced. I made the mistake of not going to the hospital at the first sign of labour with my second and nearly had her in the car. The actual labour was longer - 3 1/4 hours, but I only made it to the hospital by the skin of my teeth and the doctor wasn't there or anything..
My advice is go to the hospital at the first sign of labour! The first real contraction!