Harbor City International School, also known as Harbor City or HCIS, is a charter secondary school in Duluth, Minnesota, United States, that opened in fall 2002.

The school is governed by an eight-member board of directors.

[2] The school opened in 2002 on the third floor of a 19th-century plumbing supply warehouse in downtown Duluth, which was renovated to provide expandable instructional spaces, "cave" and "get away" spaces, and support for project-based learning.

The adaptation received a 2002 DesignShare Award.

Two years later the school expanded onto the fourth floor and doubled its enrollment to about 200, and in 2008, with the assistance of a grant, added performance space on the second floor.