This chapter recounts the founding of the Iguazú National Park in Argentina in 1934. It shows how the goal of securing and occupying Argentina’s border zone through the use of a national park overcame the conservationist belief that the park’s mission was limited to the protection of flora and fauna. After the settlement of the Argentine border disputes with Brazil and Chile in the last decade of the nineteenth century, the country witnessed a proliferation of plans for the development of its borderlands. The chapter describes how, with the failure of the initial border colonization plans, local politicians and businesspeople began proposing national parks as an alternative tool for the settlement of the borderlands. This chapter and the next (Chapter 2), ultimately demonstrate how geopolitics and the drive to occupy what was seen as an empty borderland led to the establishment of national parks at the Argentine-Brazilian border in the 1930s.