The newest parts of Earth's crust are primarily located at mid-ocean ridges, where tectonic plates are diverging. At these locations, magma rises from the mantle to create new oceanic crust as tectonic activity pushes the plates apart. The Mid-Atlantic Ridge is one of the most prominent examples, running down the center of the Atlantic Ocean.
Additionally, hotspot volcanoes, like those found in Hawaii, can also create new crust as magma erupts through the surface, forming new volcanic islands. Overall, the creation of new crust is an ongoing process predominantly occurring at divergent plate boundaries and volcanic hotspots.