As borders weaken, boundaries across the world, including the U.S-Mexico border, have become centers of large-scale cities. In the contemporary “trans-frontier” metropolis, infrastructures of control articulate otherness, and spatially and economically separate communities. While historically, diverse social groups have moved across these border territories, practices of control remained fluid and ever changing. However, trans-border urban societies challenge the separating function of the border via new social and spatial interactions, defined by interdependent economic and ecological forces.
Border regions like the San Diego / Tijuana region share watersheds, water treatment solutions, atmospheric conditions, and strategies around energy production and consumption. Thousands of commuting Mexican workers cross daily into San Diego to work in the manufacturing and service sector while US citizens regularly venture into Tijuana for shopping and recreation. Michael Dear describes the border metropolis as a “third nation” whose identity is shaped by daily protocols of the border and strengthened by transnational cultures of protest that have sparked their own cross-border communities, discourses, and imaginaries. As a result, people in border regions are less divided by the border than they are unified by “vertical relations of power and horizontal bonds of mutuality,” unifying the ‘twin cities on opposing sides of the border into a single transcultural entity negotiating a ‘border commons’.
The framework of border as commons presents an exciting territory for architects and urbanists, ranging from considerations of the border as productive infrastructure to public space activism:
“How are questions of identity, legality, and rights as well as exclusion, violence, and protest affected by the dynamics of borders?”
Study Architecture 
ProPEL 
