Lockpicking is a class skill in WoW Classic that only Rogues can learn. A high skill in Lockpicking allows your character to pick locks on chests and doors. To increase your skill in this ability, you need to level up Lockpicking. This WoW Classic Lockpicking Guide explains how to level Lockpicking from 1 to 300.
Leveling Lockpicking in Capitals in WoW Classic
In WoW Classic you can offer your services to pick locks as a
Rogue in a capital city. To do this, create a macro that you can use to post regularly in the chat. If your Lockpicking skill is very high, you can even charge gold for it or receive tips more often. This is particularly useful if you are standing in the city and, for example, waiting for an Onyxia head to be redeemed for the buff or have other downtimes.
While this isn’t a quick way to level up Lockpicking, now and then you’ll get chests that still give a skill point. Especially at the start of a new season in which many players level their characters at the same time.
Leveling Lockpicking from 1-90 in WoW Classic
To level up your Lockpicking class skill as a Rogue in WoW Classic from 1-90, the Redridge Mountains are suitable for Alliance players and The Barrens for Horde players.
Alliance Lockpicking in Redridge Mountains
As an Alliance player, go to the location marked on the following map in Redridge Mountains. When the Practice Lockboxes turn gray, you will find more in Lake Everstill (starting from skill level 70):

Horde Lockpicking in The Barrens
As a Horde player go to the ship in The Barrens where the
Rogue quest takes place:

You can level your Lockpicking skill higher than 90 in these places. Feel free to level your Lockpicking skill until the Practice Lockboxes are gray.
AdLeveling Lockpicking From 90 – 170 in WoW Classic
To level Lockpicking from 90 to 170 in WoW Classic, you can pick one of the following spots:
Use these spots to level your lockpicking skill to 170. You have to fight some enemies in all of the places and the Practice Lockboxes are relatively scarce.
Leveling From 170 – 200 in WoW Classic
The best place to level your Lockpicking skill from 170 to 200 in WoW Classic is in Badlands. Go to Angor Fortress south of Uldaman. Until 175 you open the chests in the upper part of the fortress, then the chests at the bottom.

Leveling Lockpicking from 200 – 250 in WoW Classic
You can level Lockpicking up to 250 in WoW Classic in Searing Gorge. You’ll find the lockboxes in an underground section. This is the same section where the Thorium Brotherhood quests lead you to. In the screenshot below you can see where the section is on the map of Searing Gorge:

Leveling Lockpicking From 250 – 300 in WoW Classic
To level Lockpicking from 250 to 300 in WoW Classic, you can open doors in Blackrock Depths. Enter the instance and open the following 3 doors and an optional lock:
Then leave the instance, reset it, and start again. Remember that you can only reset an instance 5 times per hour. Either you take a break or extend your run to gold farming.
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