The change of initial fr- to hr- in Arm. loans from northwestern MIr. is well attested in numerous examples (Arm. hraman, hrask, hrestak etc., Arm. Gr. 182 et seq.) and in the name of the river Hrazdan, which flows through modern Erevan and which may have received its name from Zoroastrians, for the body of water called Frazdan is referred to in the Phl. Sahristaniha i Eran as a place where Vistaspa received instruction in the Good Religion.