What were the traumatic things that were seen by Siddhartha when he travelled the city with his charioteer?

One day Siddhartha persuaded his charioteer to take him to the city. In the city, he saw different things that changed his life significantly. In the city, Siddhartha saw an old man, a sick man and a corpse. These sights were very traumatic for him as he saw these things for the first time in his life. He also saw a homeless mendicant who had adopted the path of asceticism.