Mini Motorways: How to Completely Break High Road Count Challenges

For the daily challenge on July 22, 2021, the player is given 500 roads and 1 bridge with no upgrades, and the benefit that building will stay as squares. The five hundred road allow for the entire map to be blocked in as seen below, allowing for the controlling of building an house spawn.

The first step when spawning in is to block of the entire map before the second house spawns in so you can control its spawn location, an important thing to note is that houses will never spawn adjacent to the entrance of the building and that using road in sets of two is the most efficient way to block the area. Also at a certain point you likely wont be able to pause before the houses spawn, but that is irrelevant.

Shortly into the game the borders should start expanding, I believe that it is faster than normal as it wants to spawn a new factory, but i’m not certain.

You can hold RMB to seen exactly when the border expands, and should aim to pause the game as soon as the happens then add roads to block it in.
As the player continues to block the field the rate of job requests from the building will increase, in order to counteract this when need to spawn housing in a line, which is a simple as leaving the space open for them to spawn.
As the number of housing increases the timer should end up stuck at around 50 percent, never being able to fill up. To further improve efficiency as you go the closer houses should be removed from their connections to allow for faster speeds on average on the road.

At this point the current set-up can likely keep running forever, but there is still a chance of a build up occurring and destroying the run.

To prevent this we flip the houses around to bottom and remove more close houses from the road. This reduces the amount the cars have to stop while heading to go take trips thus improving the efficiency.
Once you have a full set of houses on top of the road you can remove a few more houses at the front to lower the slowdowns even further.

At a certain point the map stops expanding this means you no longer have to look at the game to play it as it will run infinitely. At this point the best decision it likely to try and duplicate the set-up with spawning more factories so the trip counter increases faster, but that might lead to failure.

When you have reached the end your map should look something like this:

I left mine running for somewhere around 6 hours and ended it at a score of 27352, but it could have kept going for a quite a while.

Circular building have no significant effect on the strategy

The only real downside is that you can’t actually idle this set-up unless the upgrades are disabled, but that is only a minor problem, go set-up an auto-clicker or something.

July 22nd: This challenge was fairly easy to set-up as the 500 hundreds road allow for enough room to control the spawns of houses.

July 23rd: This challenge is significantly more difficult the 150 road limit reduces the control of the player on house spawn location making it much harder, but the double starting spawn somewhat mitigates this problem. At some point due to the way the parking lot functions the two inputs will conflict in the parking lot and destroy the run, this can only really be avoided by luck.
July 24th: No road modifier
July 25th: roundabouts can also be used to block
July 26th: Negative road modifier
July 27th: No road modifier

Week of July 18-24: Roads not in modifier
Week of July 25-31: Roads not in modifier