OS Boundary-Line - GPX file download

Converted from the October 2023 issue, released October 2023 by Ordnance Survey

Historic Counties of England, Scotland and Wales
Ceremonial Counties of England, Scotland and Wales
Administrative Counties of England
Districts, Boroughs and Unitary Authorities of England, Scotland and Wales
English Civil Parishes and Welsh Communities
Unparished areas
High Water Mark (useful for some coastlines)