Complex sentence: Seoul International Fireworks Festival is held from a private institution, Hanhwa, although there are many festivals that are held from the public institution like Busan International Fireworks Festival and Pohang International Lights Festival.
Split into simpler sentences: Seoul International Fireworks Festival is held from the private institution, Hanhwa. Although there are many festivals that are held from the public institution like Busan International Fireworks Festival and Pohang International Lights Festival.