Mount Monadnock, or Grand Monadnock, is a mountain in the New England state of New Hampshire. Authors such as Ralph Waldo Emerson and Henry David Thoreau wrote about the mountain, so it is well-known. It is the highest mountain between the White Mountains of New Hampshire and the Massachusetts Berkshires. It is the highest point in Cheshire County, New Hampshire. Monadnock is one of the most popular mountains to climb in the world.