Why is there no bridge over this river ?

[lz14]

See attached image.

The red circle shows there is no bridge over the river.
The blue shows there is a bridge.

Can someone help to explain why ?
Thanks in advance.

 

[Oberinspektor Derrick]

No real idea, but bridges are a product of being classical roads or better.
My hypothesis is that since you do not own the other tile across the river, it might be that the western road tile (unclaimed) was created in the ancient era and still is an ancient era road, while the eastern road tile (claimed in your territory) has been updated to a classical road (or better) as you have progressed in tech past the ancient era.
Claiming the western tile should likely fix it.
Do test it though, I'm curious if my hypothesis holds true.

 

[lz14]

No real idea, but bridges are a product of being classical roads or better.
My hypothesis is that since you do not own the other tile across the river, it might be that the western road tile (unclaimed) was created in the ancient era and still is an ancient era road, while the eastern road tile (claimed in your territory) has been updated to a classical road (or better) as you have progressed in tech past the ancient era.
Claiming the western tile should likely fix it.
Do test it though, I'm curious if my hypothesis holds true.

Thanks for the reply.

I had the same thoughts and tried it before, it doesn't fix it.

It might still be the reason, but I would think that's a very common thing to happen, this early in the game, surely it would have been noticed ?

 

[Oberinspektor Derrick]

Could be a bug as well of course, maybe you need to run another trade route across that path to update it?
Or it could have something to do with someone else running the trade route (creating the road) that is on another tech level than you, I'm really not sure though.

 

[MrRadar]

The road on the unowned jungle tile visually is still Ancient Road, it hasn't been upgraded by a passing trader from a more advanced civilization yet, so no bridge there. If a trader would travel over that tile now, the bridge would appear.
Buying or acquiring that tile naturally will not upgrade the road automatically the same turn, roads within your territory upgrade only on the turn when you reach the upgrade era for the roads: Classical, Industrial or Modern. Otherwise, if a more modern trader passes or if you build a more modern road or railroad there yourself with a builder or ME.

 

[Lonecat Nekophrodite]

this road was a trade route of previous era. and not being used rightnow.
so far you didn't research Military Engineering (?) technology yet (to train Engineers to build roads).

from what I saw you are training a merchant in Sao Paolo, once done, hook a trade route from there to Rio, and you'll get a bridge across this river to the left.

 

[lz14]

The road on the unowned jungle tile visually is still Ancient Road, it hasn't been upgraded by a passing trader from a more advanced civilization yet, so no bridge there. If a trader would travel over that tile now, the bridge would appear.
Buying or acquiring that tile naturally will not upgrade the road automatically the same turn, roads within your territory upgrade only on the turn when you reach the upgrade era for the roads: Classical, Industrial or Modern. Otherwise, if a more modern trader passes or if you build a more modern road or railroad there yourself with a builder or ME.

Thanks for the replys guys,

I understand now.