There are 15 autonomous Sun Dome Temples of the Yelmalio cult. The temples are uniformly shaped, although many vary somewhat in surprise. The most important Sun Dome Temples are generally considered to be that of Dragon Pass (in Sartar) and Saird (Mirin’s Cross).
Each Sun Dome Temple is autonomous, and have subsidiary temples and shrines. In the past, some individuals have temporarily unified several of these temples under their personal leadership, especially if they held the legendary Orb of Sovereignty, but this is an exception rather than a rule.
See also 15 Sun Dome Temples.
What is also clear is how important the cult is in the Lunar Provinces. There are some 72k Yelmalio cultists in the Lunar Provinces, clearly the vast majority of cult members. In Holay, there are 40k Yelmalio cultists – making it as large as the Orlanth cult (but still significantly smaller than the Seven Mothers cult in that province).
Historically, Jannisor’s Rebellion included the Sun Dome Temples of Saird, allied with the Sable Tribes, and the many Orlanthi tribes surrounding Saird. Likely the Sun Dome Temples were part of the Kynnelfing Alliance that resisted but ultimately was defeated by the Conquering Daughter. The Sun Dome Temples fought on all sides of the wars during Third and Fourth Wanes, but have been mostly allied with the Lunar Provincial Government since the Sixth Wane.