The black rat snake is one of the most common large black snakes you will find, they are nonvenomous and fairly docile but will bite when they feel threatened and vibrate their tails like a rattlesnake. I have found them up to 6.5 ft long, roughly 2 meters.
They are a great form of natural rodent control, a large one will even eat a small squirrel on occasion. They are great snakes to have around and so beautiful. Comment any questions you may have and I'll see if I can answer them.