Hello everyone!
Here is a screenshot of the graphical glitch:
I play on the giant earth map. Civ 6 + all DLC and YnAMP mod. No any other mods.
All available nations are in the game.
I've played more than 850 turns. The glitch appeared at ~700 turn. The whole map has been revealed way before that and there was no such artifact in that area or anywhere else.
Here is what I have found so far:
1. The glitch is not there when I load my save. It only appears after 2-3 turns.
2. The glitch is not fixed. It changes its form a bit but it is always at that area.
The area is right at the west/east border of the map which might be helpful.
3. Changing graphic settings and reinstalling nvidia drivers doesn't help.
4. I turned off all the other software such as antivirus, messengers and so on.
System specs:
i7-3770K
16gb ram
8GB 1070 Asus dual (latest nvidia drivers are installed)
Win7 64bit ultimate + all Windows Updates installed.
Game settings set to medium and all the effects (blur, occlusion, etc...) are disabled. except for AA set to 2x. As I said changing them doesn't help.
Since I have installed the game I never did any changes to my pc. No new software or hardware has been installed.
Here is a screenshot of the graphical glitch:

I play on the giant earth map. Civ 6 + all DLC and YnAMP mod. No any other mods.
All available nations are in the game.
I've played more than 850 turns. The glitch appeared at ~700 turn. The whole map has been revealed way before that and there was no such artifact in that area or anywhere else.
Here is what I have found so far:
1. The glitch is not there when I load my save. It only appears after 2-3 turns.
2. The glitch is not fixed. It changes its form a bit but it is always at that area.
The area is right at the west/east border of the map which might be helpful.
3. Changing graphic settings and reinstalling nvidia drivers doesn't help.
4. I turned off all the other software such as antivirus, messengers and so on.
System specs:
i7-3770K
16gb ram
8GB 1070 Asus dual (latest nvidia drivers are installed)
Win7 64bit ultimate + all Windows Updates installed.
Game settings set to medium and all the effects (blur, occlusion, etc...) are disabled. except for AA set to 2x. As I said changing them doesn't help.
Since I have installed the game I never did any changes to my pc. No new software or hardware has been installed.