How to change a Race track path but keep the same map

Hi all.
I’m thinking how to implement this:
I have a map with some roads and city blocks, and I want to create a race track path (track 1) on this map.
So for example when the player complete the track 1, I want to change the track path to another one (track 2), which is different from track 1 but on the same map.
(this is a common practice in a lot of race games)

So how and where I should manage this in order to utilize the map?

Thanks!! :slight_smile: