I am not sure we are talking about the same thing. Prayer is supplication, at least in the Orthodox world. For instance, the liturgy on Great (Holy) Saturday, the Orthodox walk around the Church three times, carrying the symbolic coffin in which Jesus is buried, icons and candles and sing "Christ is risen from the dead, trampling Death by death, and upon those in the tombs bestowing life..."
It is a chant on the church gorunds, and it is not a prayer.
In Orthodox countries on certain feasts (such as the patron saint of a city), there are processions . The procesison consists of caryring icons and crosses and flags in silence through the city. Likewise, there is no prayer. No different than marathon or walkathon.
Savior's Day, the Day of the Ascention of the Savior, Pentecost. Belgrade, Serbia
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