Mention London, Rome, or New York, and people immediately conjure up Big Ben, the Colosseum, the Statue of Liberty. Beijing, Cairo, Mumbai? Check. They’ve heard of them. Megacities, the ones with lots of history, lots of people, and an oversized impact on the economy and culture, tend to be well-known. 

Fewer people may know much about Addis Ababa, Dhaka, Lagos, or São Paulo — yet many would recognize the names. But who knows or has been to Darkhan, Mongolia or Santa Fe, Argentina or Boké-Kamsar in Guinea? These are all secondary cities that provide regional services such as governance, production, and transportation. These three cities are part of the U.S. Department of State’s Secondary Cities program, which is designed to build partnerships to enhance understanding through mapping and enable science-based decision making. As the project site points out, “Mapping these cities is an essential activity in building resiliency and devising robust emergency management plans.” And, because so many people live there and so much of the future of nations depends on movements that start in secondary cities, what happens there also affects U.S. national security.

What is a Secondary City?

In some ways it is easier to say what a secondary city is not. It is typically not a metropolis with millions of residents. Although population is not the best metric of a secondary city, they usually fall into the 300,000 to 5 million population range. But a secondary city in China or India is likely to be much larger than one in Costa Rica or Mexico. A secondary city is not the capital of the country or its primary economic seat, but it may be a regional or provincial capital. With a population of almost 5 million, Addis Ababa, the capital of Ethiopia, is a primary city. Mekelle, the capital of the Tigray region in northern Ethiopia, with a population of just over 300,000, is a secondary city. Maputo, the capital of Mozambique, has a population of just over a million. Pemba, a port city of over 200,000 in northern Mozambique that is also the capital of Cabo Delgado Province, is a secondary city.

Secondary cities are regionally important. They may house universities, hospitals, and other amenities that serve the surrounding area. They may be culturally or economically significant. Think of Cusco, Peru, a former capital of the Inca Empire and current UNESCO World Heritage Site, or the port city of Boké-Kamsar, Guinea, a crucial site for exports and imports. And secondary cities typically have closer economic and cultural ties with surrounding areas, compared to capital cities with their strong international connections. They may not be as famous or flashy as the megacities, but secondary cities in aggregate house many more people than the megacities—simply because there are many more of them.

Advantages  

According to the most recent World Urbanization Prospects, only about 7 percent of the world’s inhabitants live in megacities of 10 million or more. And as the World Bank notes, historical factors in urban development mean that “physical form and land use patterns can be locked in for generations.” This is especially true in the largest cities, such as Lagos, Nigeria, resulting in long-lasting and unsustainable sprawl. Because of the magnitude of these problems, they can be nearly impossible to quickly address. In contrast, secondary cities, further behind on the infrastructure development curve, remain much more amenable to sustainable development that is better for both human residents and the environment. And even if migration out of rural areas seems inevitable, it does not have to lead to megacities, where it often results in poorly-planned expansion and the growth of slums.

Vibrant secondary cities are also a crucial component that  support internal migration and help in humanitarian crises involving internally displaced people, such as in Kharkiv, Ukraine. Secondary cities can become “jumping off” points when people move from secondary cities to megacities due to a lack of sustained economic activity. Although many governments have tried to reduce rural-to-urban migration, such policies have largely been ineffective, only serving to hide poverty, often with undesirable human rights impacts. Secondary cities can also be important in the international migration process. For example, Esmeraldas, Ecuador is the primary port for Ecuador’s oil exports as well as a transboundary destination for international migrants, particularly from Colombia and Venezuela. By helping integrate migrant populations, secondary cities can also reduce social strife and increase well-being for long-term and new residents alike.

Under-examined Spaces

The data and information needed for city planning and national policy development are often lacking for secondary cities. Focusing on 16 cities around the world, the U.S. Department of State Secondary Cities Initiative created data to support local emergency preparedness, human security, and resiliency. For example, Douala, Cameroon, was the location for a partnership with the USA Cameroon Chamber of Commerce, Douala Institute of Technology, and the Municipality of Douala that studied sea level rise and climate change adaptation, a major concern for many coastal cities. Similarly, in Denpasar, Indonesia, the project generated data on waste management, an important issue around the world. The 16 cities showed more commonalities, on issues like modified hydrology, urban fauna, and transportation networks, than differences resulting from their unique geographies.

Looking Ahead

Cities offer jobs and services that draw people from near and far. Efficiencies of scale and improved technology also mean that the environmental footprint of urban individuals is smaller. Although the focus has been on how these phenomena play out in primary cities, they are also crucially important in secondary cities.

Secondary city economies tend to be more specialized and can respond differently. For example, secondary cities with strong international ties, such as tourism in Cusco or commerce in Kamsar, were harder hit and had fewer resources for responding to a major crisis such as the current COVID-19 pandemic. Closer ties with rural areas mean secondary cities may be important in further spreading the disease, but also potentially important in preventing such spread. And the collapse of services in these cities can more drastically impact surrounding communities.

Conversely, improvements in services and resiliency of secondary cities can positively affect large areas that intimately rely on them. And, because they don’t suffer from the inertia that size and expansion history impart to primary cities, secondary cities offer greater return on development investment. For security and other reasons such as cost effectiveness and humanitarian impact, both national and foreign development agencies need to more heavily invest in understanding and improving conditions in secondary cities, which currently receive surprisingly little attention.