A promontory is a prominent mass of land which overlooks lower lying land or a body of water (when it may be called a peninsula or headland).Most promontories are formed either from a hard ridge of rock that has resisted the erosive forces that have removed the softer rock each side of it, or are the high ground that remains between two river valleys where they form a confluence.Throughout history many forts and castles have been built upon promontories because of their natural defensive properties. The promontory forts in Ireland are an example of this.A promontory often has a shape resembling that of a nose. This is reflected in the Scottish Highlands, where a number of hills are called Sr├▓n, the Gaelic word for nose.
Headlands and bays
Promontory Point, Utah