"Burial Tomb" is the egyptian temple and quite usefull when going wide and religious. It cost no upkeep and provides + 2 happyness + 2 faith.
By taking 3 policies in piety, the building can be built at double speed and it will give + 3 faith and +25% Gold.
It can be later enhanced by a religious belief to give +2 culture if the city has 5 followers. (It always depends on what other beliefs are still available if +2 culture is a good choice.)
-> build at double speed, +2 happiness, +3 faith, +2 culture, +25% Gold, no upkeep.