The image below is a visualisation of what you get back if you plotted the coordinates on a map.

The latitude and longitude coordinates for the perimeter of the arrival search polygon.

The latitude and longitude coordinates for the perimeter of the departure search polygon.

It means you get two lots of information: These are two different requests within a single API call.

For example, if you want to arrive at your origin location at 5pm, and travel a maximum of 30 minutes, the points returned will show the perimeter of all the places you can depart at 4.30pm to arrive at the origin at 5 pm or earlier. The arrival request assumes the reverse - you must arrive at your origin at the specified time. The standard postman assumes you need to depart at the time you make the search. For example you may depart a location at 5pm, and travel a maximum of 30 minutes, so the points returned will show the perimeter of all the places you can reach before 5.30pm. A departure request shows where is reachable, assuming you depart your origin location at a set time. The code shows one departure request (top orange arrow) and one arrival request (bottom orange arrow).

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