There was only one entrance to Tritonis. It was a large gate, set into the wall which surrounded the city.
So tall was the gate that it was five times higher than the tallest horse on the island; taller even than the shadow made when the guardsman whose mount it was sat high on the great beast in his ceremonial armour with its feathers and fur all flying up around him and across his blue skin, so that he would look like a sunset — even this guardsman and his mighty horse were dwarfed in their height by the city gate.
No one in the city could remember a time, or had even heard of a time, when the gate had been closed, and the drawbridge across the moat drawn up. The moat had never been breached. This is no surprise, because it was so full of dark fears; things that crawled and slithered and stung, or things that were the dark shadows of themselves — but about these things and the moat and its awful depths we are not going to concern ourselves, because they are another story altogether, and one much more difficult than this.