Conversation so far:
what is the capital of the country saudi arabia
Riyadh is the capital of Saudi Arabia.
what is the tallest building in riyadh
Public Investment Fund Tower is the tallest building in Riyadh.
how tall is the public investment fund tower
The Public Investment Fund Tower is a 385 m skyscraper in Riyadh, Saudi Arabia.
what is riyadh's elevation
Riyadh is located on the eastern part of the Najd plateau at about 600 metres above sea level.

Question: what other cities are in the najd plateau
Self-contained rewrite: what other cities are in the najd plateau besides riyadh