Final answer:
Many dense population areas are located near major water bodies due to the advantages in trade, industry, and transportation. Cities at break of bulk points where multiple transportation modes intersect have grown substantially, for example, New York City and Los Angeles. Agglomeration factors and globalization also contribute to the urbanization patterns.
Step-by-step explanation:
The locations of many areas with the densest populations have the common characteristic of proximity to major water bodies. This is because cities with specific site location advantages that favor trade or industry tend to grow larger. Good port facilities and varied transportation options are key factors that contribute to the growth of these cities. Moreover, cities that grew large due to such site location advantages, including New York City, Los Angeles, and Chicago, are well served by multiple modes of transportation, making them break of bulk points where cargo unloading and labor agglomeration occur. The presence of warehouses and manufacturing jobs at these points further accelerates urban growth.
In addition to trade site locations, agglomeration factors explain why economies with increasing urbanization have higher proportions of their population living in urban areas, as is the case with about 80% of the U.S. population in metropolitan areas. Conversely, in developing nations, managing the growth of cities becomes a challenge. Cities situated along coastal regions have also rapidly expanded, driven by globalization, trade agreements, and economic unions that facilitate networking trade and commerce activities.