The twenty-fifth lecture in Doug Allen's History of Urban Form series addresses a grand expansion of the Western world. It continues the story of European colonial expansion into the New World and early development in cultural hearths throughout New England, the Mid-Atlantic, and the South. The primary focus is on the United States' westward expansion through the National Land Ordinance of 1785 and the influential processes that helped shape the continent.

The twenty-fourth lecture in Doug Allen's History of Urban Form series explores the concepts of "streets" and "roads." The transition of streets as "spaces of flow" had a huge impact on the American landscape, which Doug shows in a series of comparative maps.

The twenty-third lecture in Doug Allen's History of Urban Form series continues the story of colonial cities in the Americas. It concludes Lecture 22's examination of colonial enterprises and the influence of French trading routes and settlements on North America, especially in New Orleans. Doug then continues to explore English colonies and the distinct differences between New England, the Mid-Atlantic, and Southern processes and forms.

The twenty-second lecture in Doug Allen's History of Urban Form series crosses the Atlantic Ocean from European and Old World cities to the establishment of New World colonial cities. It begins with a continued discussion of London's residential squares, primarily Bedford Square, and the importance of that tradition on British and American cities. It continues with an exploration of the processes and forms that European colonial powers planted in North and South America.

The twenty-first lecture in Doug Allen's History of Urban Form series addresses London, England, and that city's pattern of residential squares. It resumes the discussion of Europe in the Renaissance-era, but explores the differences that made English and British urban patterns unique. It begins with a history of London, the development of the Inns of Court, the impact of the Great Fire of 1666, the importation (and lack of implementation) of Renaissance cities, and the influence of London residential squares on later cities.

The twentieth lecture in Doug Allen's History of Urban Form series travels from Europe to cities in the Islamic World. It explores pre-Islamic, Islamic, and planned cities in the Middle East, North Africa, and Central Asia. The lecture also describes unique elements of Islamic cities, including caravanserai, bazaars, baths, and housing, especially in Sana'a, Yemen.

The nineteenth lecture in Doug Allen's History of Urban Form series continues the discussion of Louis XIV and Andre Le Notre's development of Versailles, France. It discusses the history of Paris and Versailles as capitol cities, the relationship of Versailles in the regional landscape, the Italian Renaissance and Rome's influence on the palace and grounds, and a diagrammatic dissection of the Versailles' grounds. This lecture also has an important discussion of the nature of "nature" and the relationships between garden, city, and nature.

The eighteenth lecture in Doug Allen's History of Urban Form series continues to explore the development of Renaissance principles in France. The lecture finishes a discussion of Paris' royal places. It then moves to the Chateau d’ Richelieu and Versailles as examples of new French "villas" that incorporated and advanced emerging city ideals and new urban forms.

The fifteenth lecture in Doug Allen's History of Urban Form series continues the Italian Renaissance and Europe's transition into the modern world. It concludes the previous lecture's discussion of Florence's early Renaissance works, including the Uffizi and Ponte Vecchio, before returning to Rome to see Michelangelo's Campidoglio and the impact of the Reformation on that city.

The fourteenth lecture in Doug Allen's History of Urban Form series is a seminal moment that addresses the shift from the Ancient and Medieval worlds to the Modern world via the Italian Renaissance. This lecture explains the evolving political (exemplified in Siena) and economic (shown by Florence) frames in Italy and their influence on the concepts of the Ideal City. The lecture also explores the invention of Perspectival Space in art history and its influence on architecture and urban design.