The northern city limits are demarcated by the lower reaches of the Resurrection River, but extend east past the river's mouth at the northern end of Resurrection Bay to include parts of the bay's extreme northeastern shore, including the beach at the mouth of Fourth of July Creek and the grounds of Spring Creek Correctional Center just inland. To the south, the city limits extend to the unincorporated community of Lowell Point, while the east and west sides of the city are constrained by Resurrection Bay and the steep slopes of Mount Marathon.