Accessibility and Nodes

Urban theory pretty clear that you have the highest land prices in the most central place. (Actual distances largely irrelevant to to what is most central, as access depends on transportation). So 'crossroads' inevitably have the highest local access anywhere you go. Empirical research pretty clear that trip frequency is inversely proportional--if something is half as far, you make 4x as many trips; if something is twice as far, you make 1/4 as many trips. How 'far' that trip is is a function of the 'cost' of at trip (in terms of cost + time). If something lowers transportation costs less (in time or money), you don't make more trips, but you tend to make longer trips. Lower transportation costs means you can do things like skip over the local market to go to the supermarket (which has better selection) or go to Walmart and get both groceries and household supplies. Lower transport costs also mean you are willing to have your house be further away from things. Further away means lower rent or--for the same money, more space (property or square footage). 

Urban land prices tend to decline as you get further from a central point. For any distance (d), the he coefficient (c) in the 1/d^c equation is set by transportation costs. The bigger that value gets, the easier it is to travel. Now, the equation suggests a smooth (if non-linear) decline from the central place. Which any realtor can tell you is crank--it's being next to a freeway that matters. Which brings up an important point--access points. A network defined by node access points (freeway exits, stations) doesn't spread access equally. It declines as you get further away, just as from the main central point. So in any urban environment, land values have a central 'peak' that declines, interrupted by smaller peaks around sub-centers, located near the point access points of the network. 

In urban land use, different uses are willing to pay more for access. For roads, it can generally be thought of as office, retail, housing, industrial, farms. Office uses will snaffle the locations near the most accessible freeway exits, retail will take the next tier down. Industrial needs big lots, so they'll typically snaffle the next tier before residential (subdivisions) have a chance.