It would be worth trying to clear your browser's cache as this might help - multiple copies of your route are stored in your browser's cache so that you can undo changes and reload unsaved routes, so it could be that your cache is very full. You could also try a different browser. Other than that I'm not sure what else to suggest. The best thing to do would definitely be to break the route into smaller more manageable segments.
Agreed, except I have modified long routes in the past and have not experienced such a delay. 10 - 15 seconds, yes but 1 - 2 minutes......
A 500km is likely to be made up of tens of thousands of points, so you would need a very fast computer to process this amount of mapping data quickly. If possible it would be better to break your route up into smaller segments.
I have been trying to adjust a 500k route I have been planning. Mapping is loading unusably slowly (I have a very fast connection). Also using the 'replot a route' tab. It allows me to replot the section, showing the new route. When I confirm the screen freezes and then after at least 60 seconds or more it unfreezes and replaces the route with a straight line. Hopefully this is a temporary problem as if it continues I would have to change to an alternative mapping site which I really do not want to do!
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