title: Automated traversing of region by longitude/latitude
body: <p>I'm trying to iteratively traverse the United States in 1 mile increments using latitude and longitude coordinates. Essentially, once I start (lets say in Portland, OR), I want to move south in one mile increments until I reach the southernmost boundary of the United States that is of the same latitude as Portland, OR. At this point, I want to start back at the northernmost part and move one mile east, repeating the entire process until I get to the east coast. I need to aggrigate these longitude/latitude points in a database. </p>
  
  <p>My question is: Is it accurate to step through latitude and longitude by calculating the next lat/long pair using a delta of 1 mile each time, or are there simpler and more elegant methods to achieve my end goal?</p>