"4.5平方公里" translates to "4.5 square kilometers," which is a unit of area measurement commonly used in land and urban planning. This measurement indicates the size of a space, such as a park, a neighborhood, or a piece of land. To visualize it, 4.5 square kilometers is equivalent to about 1,100 acres. In practical terms, an area of 4.5 square kilometers can accommodate various developments. For instance, it could house several sports fields, a small town, or a large shopping center. Understanding this measurement helps in assessing land use and planning for infrastructure in urban environments like 城市 or 社区.