The south shore is mostly flat and sandy, while the north shore is hilly and rocky. There are many other features, and they all have a story. In the center of Long Island, there is a long, hilly ridge called a moraine. Hempstead Plains and most of the south shore is made up of flat, sloping stretches of land that are outwash plains. Lake Ronkonkoma and Lake Success are kettle lakes.
Some large boulders are erratics.
Two huge erratics on Long Island are Target Rock and Shelter Rock. There are also ground moraines, such as Port Washington peninsula. Just knowing what they are is not enough. About 22,000 years ago, a glacier crept up and covered the northern half of Long Island. The glacier stopped there for a while.