You need the following skill to be able to perform this method of farming XP.
 
It's recommended to bring some Medicine, Immunity Boosters, UV Bars, and Molotovs. Not mandatory, but useful in case you get overwhelmed by volatiles and virals while performing the method. You will see what I mean further down below, when I start talking about the nighttime bonuses.
 
I really recommend to wear armor that grants you bonus percentage for parkour xp!
 
If you BOUGHT the Ultimate Digital Pack of the game, you should have a one time use of the Nightrunner Potion. The effect lasts 2 in-game hours and will grant you 100% more XP, or simply said, a stacking 2x bonus XP multiplier on top of any other multiplier like the ones during the nighttime.

You can redeem the Nightrunner Potion from any of Aiden's Stashes located in the safe zones.
 
Now this might be more risky, but with higher risks come higher rewards, right?
This is totally optional by the way, but it will greatly increase your Parkour XP gains. There are two variants of this!

Variant #1 (Difficulty: Easy):
Wait for nighttime to come and start doing your parkour. You will get 2x bonus XP after the night ends. No need to start chases!

Variant #2 (Difficulty: Hard):
Go down on the streets, just next to the building where you will be doing your parkour, and find some Howlers. You want to trigger their alerting reaction in order to start a chase. Now quickly go up the building again and start doing the parkour. As the chase levels increase, so will your bonus XP multiplier.

Chase Level 1 will NOT affect your bonus XP multiplier! The multiplier stays at 2x, just like when you are not in a chase during the nighttime.
 
 
Chase Level 2 sets your bonus XP multiplier at 3x!
 
 
Chase Level 3 sets your bonus XP multiplier at 4x! At this point, usually, there will be at least one volatile coming at you. Stay alert and make sure to have the items, listed earlier above, ready to use!
 
 
Chase Level 4 sets your bonus XP multiplier at 5x! The number of volatiles increases!

 
 
Tip! If you are fast enough when performing the far jumps, the AI of the zombies will get confused and they might just stay in one spot most of the time. This will decrease the odds of them attacking you.

Tip! When you are finished with your parkour gains, quickly run to the nearest UV light/safezone to end the chase! It is important not to die, or else you will LOSE your bonus nighttime XP!

You will have to go the location shown in the image below.
For your information, this is located in Old Villedor!

Go to where the green dot is on the enlarged part of the map!
This is what the location looks like, what you will be using is the two vault spots highlighted in green!

It's simple, just far jump from one vault to another. Rinse and repeat!
 

I hope that you enjoyed my guide on how to quickly farm parkour xp. It's been my pleasure helping you out people, it is also really fun working on new guides!
 
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