peninsulated

Eccliscraig, formerly a place of great strength, being erected on a perpendicular and peninsulated rock, sixty feet above the sea, at the mouth of a small rivulet.

The Mirror of Literature, Amusement, and Instruction Volume 10, No. 280, October 27, 1827 Various

Other continents are somewhat peninsulated; Asia approaches Europe in that respect; North America has a few great dependencies in its larger islands and considerable promontories; but Africa, South America, and

Introduction to the Science of Sociology Robert Ezra Park 1926