Yoida Full Gospel Church, Seoul S. Korea.
On the day in 2010 that I visited the church, I estimated from the size of the building, and the number of services, that around 150,000 people attended in that room. I am told that there were other rooms where staff (Sunday school etc) had a remote link. Also there were other satellite congregations on remote link. The founding pastor, Yonggi Cho, preached and led communion.