Explore Heard Island and McDonald Islands - A Nation of People. Heard Island and McDonald Islands (HM) is a diverse and thriving country spanning km² ( sq mi). With a population density of people per km², it offers a unique blend of cultural heritage, economic opportunities, and breathtaking landscapes. Whether you're interested in tourism, business, or history, Heard Island and McDonald Islands stands out as a global destination. Stay informed about Heard Island and McDonald Islands’s geographic insights, demographic trends, and more. Discover why Heard Island and McDonald Islands is a key player on the world stage today!