topography

• 地势平坦

  smooth terrain

• 地势崎岖不平

  rugged terrain

• 地势险要

  inaccessible place

• 这地方，山高林密，地势险要。

  With its high mountains and dense forest, this is a very inaccessible place.

• 房子的地势很低。

  The house is situated on low ground.