What is the fine-grained topic of the following text: What’s great for the purposes of mapping our urbanism is that these maps (excerpted from the new Technical Paper) give us an accurate and uptodate view of the extents of the city and greater region as it is essentially right now, and also how the extents of current development fit into the protected land of the greenbelt. Only return the topic.
Urban mapping and its relationship with protected greenbelt land