Regla is the centre of Santería practice in Havana — the Afro-Cuban religion that fuses Yoruba spiritual practices with Catholic iconography, brought to Cuba by enslaved Africans and their descendants. Walking through Regla on most days you will see people in white (orishas devotees in the first year of initiation), religious paraphernalia in shop windows, and houses with altars visible through open doors.
The neighbourhood's association with Santería predates tourism and is entirely genuine — this is not staged for visitors. Respectful observation is welcome; photography of religious ceremonies or private altars is not. Regla is one of the few places in Cuba where Afro-Cuban religious practice is visible as an everyday phenomenon rather than a cultural performance.