The overall continental boundary of mainland Africa queried from rnaturalearth and get processed.

mainland_africa

Format

A sf with one rows and 2 fields

name

(character) The name of the polygon: Africa

area

(units) The united number of the overall area in km2. This is not a consensus area, but just a calculated area under this resolution.

geometry

(sfc) The simple polygon feature of the boundary

Source

rnaturalearth