The Sun Altar room is a forgotten part of the original basement of the Leyendecker Museum. A secret Cult of Amon Ra, led by Rameses Najeer, uses this room for secret meetings and ceremonies. Yvette Delacroix showed Najeer this secret room, and let him use it to conduct the ceremonies.
As it is a secret room, the only entrances and exits are through secret doors. One known secret door leads there from the Mummy Storage room. Another leads to the Furnace Room.