There was a starting point at each of the respective base camps which was completely enclosed. The players were given a minute of preparation time. During this time, they were able to get their food ready, cancel any debuffs and buff each other.
If you looked through the closed gate, you could almost see the opposite base camp.
Both base camps were elevated while the middle of the battlefield was quite low; this was why the battlefield was called a basin. At the foot of their base camp was the Pound while at the corresponding position on the Horde's side was the Farm. The Blacksmith was in the middle of the battlefield and the two sides had the Sawmill and the Mines.
The Sawmill were higher up, while the Mines were quite low.
It could be said that Arathi was a very well-designed battlefield that took into account the positions and altitudes of each of the locations. Each side could make use of the water, the cliffs and the line of sight.