In Final Fantasy XIV, the starting city for Gladiators is Ul’dah.
Ul’dah is a desert city-state in Thanalan and one of the three starting locations in Final Fantasy XIV: A Realm Reborn. Players who select Gladiator as their initial class begin their adventure there, close to the Gladiators’ Guild and the Coliseum. The city’s gladiatorial culture fits the class’s identity as a one-handed blade and shield fighter who protects allies while controlling enemy attention.
The main alternative answers are the starting cities of other classes. Limsa Lominsa is associated with maritime life and is the starting city for Marauders and Arcanists, while Gridania is the forest city associated with Archers, Conjurers, and Lancers. Ishgard is important later in the story but is not one of the original class-start cities.
At level 30, a Gladiator can undertake the required class quest and advance into the Paladin job. Thus, Ul’dah is the correct starting city, while Paladin is the later combat specialization rather than a separate starting class.