Reading Senior High School, colloquially known as The Castle on The Hill, is a 9–12 public high school in Reading, Pennsylvania. It was established in 1927 and is part of the Reading School District. With an enrollment of 5,213 as of the 2022-23 school year, it is the largest traditional high school in Pennsylvania and one of the largest high schools in the nation.

A state school, public school, or government school is a primary or secondary school that educates all students without charge. Such schools are funded in whole or in part by taxation and operated by the government of the state.