Rectangles on Google Maps display a rectangle shape. For your wordpress site you can activate the WP Google Map Pro plugin to display such rectangles (like the one in map below) between any set of locations using a easy to use drawing tool. The plugin will also enable you to customize the style of rectangles,fill color, stroke color, stroke weight etc.
This google map wordpress plugin is available on codecanyon to get it.
Customize Product according to your requirements?
We will be glad to discuss any of your needs related to our wordpress plugins . if any of functionality you'd like to see in products, you can reach us by via email email@example.com.