Definition of "promontory"
A high point of land extending into a body of water, headland; cliff.
Quotations
South of Hang-chou Wan (Bay) below Shanghai, the China coastline changes from a smooth, flat topography to one of irregular, rocky promontories and numerous islands. Foochow, the Fugiu of Marco Polo, dates from the seventh century. Offshore the Ma-tsu Lieh-tao (Matsu and Pei-kan, or Changshu Islands) are heavily fortified Nationalist strongholds.
1970, Ken Fitzgerald, The Space Age Photographic Atlas, Crown Publishers, page 196