Due to the very poor development of the game, in terms of unrealistic physics, baffling simulations that never work properly from run to run, and numerous glitches in general this achievement is made virtually impossible. So i thought i'd post this guide for those that want 100% completion and an end to the stupid madness.

1: Build a bridge completely out of wood (inc road)

2: Make your bridge strong enough for Buses only


3: Let the buses clear the bridge successfully


Upon the following message "Actual Test 6 Cars (6t)" appearing in the centre of the screen, click edit bridge and again to test bridge as fast as possible.


If successful you should then see cars as your 1st test, then buses and cars again. It may take a few attempts, but usually it'll work within 1 or 2 tries if your quick.


Then simply exit the game to obtain your achievement, since this game is so glitchy.