I have just visited Pompeii 2 weeks ago. It is quite breathtaking and is around 149 acres. It's best to get a guide. The people did die from the gases that were released but some did not die instantly. There are a couple of bodies on display that are perfectly preserved and still shows the suffering on their face as they lay dying. It also shows how small they were. The average height was only 5ft. You will also see some theatres and explicit pictures in some buildings.