A look at most of the cities within Latin America reveals striking commonalities across countries, from Mexico down to Argentina: most cities have a well-defined area known as "El Centro" (The Center), anchored by a main plaza (Plaza Mayor), flanked by a church on one side and key buildings like the city hall on another. This is no coincidence, as it can be traced back to an urban planning system established during the Spanish colonization of the Americas in the 17th and 18th centuries. It gave standardized guidelines for city design across its viceroyalties. Unlike French and English colonies, Spanish settlements adhered to regulations that contributed to the emergence of a shared urban identity, with cities displaying similar spatial logic and architectural cohesion despite differing scales and contexts.
To advance the colonization process of the Americas, the Spanish Empire constantly needed to establish new urban centers. For this purpose, a series of laws were issued by the Spanish Crown to regulate social, political religious, and economic life in the colonized areas. In 1573 King Felipe II enacted the "The Laws of the Indies," a legislative text consisting of 148 ordinances that guide and regularize the establishment of presidios (military towns), missions, and pueblos (civilian towns). In 1680, King Carlos II compiled those ordinances and other laws under a series of documents known as "Recopilación de las Leyes de los Reinos de Indias". It is under this compilation, mainly titles six, seven, and eight, where the standard blueprint for spanish city planning in the Americas can be read in its integrity. To this day, they are considered by some historians as one of the first standardized urban legislations in the world. They specified city layouts, from the dimensions of a central plaza to the orientation of streets and the ideal elevation for a town. With their implementation, the Spanish Crown was trying to adapt to varied contexts and the specific conditions of each location to ensure the settlement's success.
The city's geographical location had a significant influence on its urban planning. In the case of coast-side cities, elevated terrains were preferred, taking into account the protection of the port, with the law requiring the city to avoid openness to the ocean to prevent pirate attacks. In practice, the coastal cities often settled on islets or inner bays, with most of them having a fortification on the ocean side. Examples of this can be seen in places like Santo Domingo in the Dominican Republic, Havana in Cuba, and other cities in south United States such as Saint Augustine in Florida or Old San Juan in Puerto Rico. For inland cities, places of medium elevation were favored, preferably near navigable rivers to allow better commerce and quick access to fresh water.
This Spanish urban model employed a rectangular grid centered around a plaza, which served as the civic heart of the city. From this central location, a rectangular grid of straight streets was planned, shaping urban areas for residential use and leaving peripheral open fields with plots, known as "Quintas," designated for future urban expansion and agricultural activities. The orientation of the grid was decided by accounting for dominant winds, to protect the Plaza Mayor. This central plaza was typically square or rectangular, with ideal dimensions of 600 feet by 400 feet, though these standards were not always strictly adhered to. This resulted in varying plaza sizes across the continent, but always maintaining the rectangular shape. Examples of this urban model can be seen in cities like Comayagua in Honduras and Leon in Nicaragua, and Quito, Ecuador.
The plaza was bordered by streets on all four sides, with two streets originating from each corner, forming the foundation of the city's grid. Today most cities have pedestrianized the street in front of the church, so when observing modern maps, only 3 streets are apparent. The width was determined by the local climate. Cold areas were required to have wide streets, while hot areas favored narrow streets. This difference is visible in a comparison of the maps of Cartagena de Indias in Colombia, located at sea level, therefore benefiting from warm weather and Antigua, in Guatemala, located in a cold climate at an altitude of 1500 m.
Along with the plaza, the law required the church to be the central focus of the new urban space. It specifically stated that it had to be built in an independent block, separated from the plaza by a street, and elevated in an atrium accessed by stairs to give it more importance. The church also had to be oriented towards the East, following Catholic dogma. The plaza would double as a civic center, hosting on its sides the required buildings for the proper functioning of the settlement like the city hall or the viceroy palace. The remaining streets and blocks were to host arcades to allow for commerce. This specific building organization is found in all colonial cities throughout Hispanic America; however, some textbook examples are Mexico City and Lima in Peru.
Today, these foundational sites are considered historic and are often referred to as "El Centro" due to their central location within the city's grid. Over time, as cities expanded and countries gained independence, the old Spanish "Quintas" gradually disappeared, making way for modern urban growth. In many cases, original Spanish buildings were replaced, yet the iconic plazas flanked by a church, remain the most recognizable urban landmarks in most metropolitan areas. For example, in Buenos Aires, Argentina, the Plaza de Mayo retains its colonial roots but now includes republican-era buildings like La Casa Rosada. Similarly, in San Salvador, El Salvador, the central plaza features a new church, built to replace the one destroyed by an earthquake in 1873.
The Laws of the Indies left a lasting legacy on the urban fabric across America. By standardizing city layouts, they ensured that all settlements adhered to a coherent vision, creating a recognizable and enduring spatial order. Today, the grid patterns, central plazas, and architectural focal points that originated from these laws continue to shape the identities of cities across the region, standing as a testament to a shared history and culture that unifies the Hispanic countries in the continent.
