How do I animate a dotted line.

My travelogues comprise of video clips, photos and maps. Is it possible to animate a graphic, a round dot for example, to show a route of travel on a map or onto a photo to show a climbing route. Someone suggested adding, in Photoshop,a dot to the map at the start of the route, save the file, add the second dot then 'save as' a different filename then repeat, adding more dots until the end of the route.  A transition between photos could then be set at a fraction of a second. This could lead to dozens of files and I suspect that there is a much better way using Keyframes but I may need to see a demonstration video of a similar project.