Pewter mueseum :D
Pewter City
take it to pewter museum
go to the museum in pewter city
go down at pewter city
talk to the man on the platform in pewter city
Its in Kanto to the right of Pewter city.
to pewter city
At the top of pewter city in the kanto region
After you get the silver wing from the old man in pewter city
You can fly there or go west.
It is in the very North western part of the Kanto region.