Red Dead Redemption 2's story mode allows players to go off the beaten path in search of secrets. Amongst them is treasure such as gold bars that can be obtained by following clues found on several different maps (or this guide). Treasure hunting is one of the typical outlaw activities, so it's not surprising to see it in included in the game.

The story mode main treasure hunts are the Poisonous Trail, High Stakes, and Jack Hall Gang treasure hunts, but there are a couple of shorter ones that can be completed quite easily if you know what you are doing.
Among them is the Sketched Map treasure hunt (what this guide is all about), and which is very rewarding considering how little it takes to complete.
Clearing treasure hunts is not required to complete the story, but if you're aiming to do everything there is to in the game, you will need to complete at least one, as it's a requirement for getting 100% Completion. Mastering the game will also lead to unlocking the game's Platinum Trophy and all of the Xbox Achievements. Finding all the available treasures is also required to complete the Explorer Challenges.
Kicking Off The Hunt
As already mentioned, the Sketched Map treasure hunt is among the shortest of the entire story mode. If you are willing to travel far from the Valentine area, you can also complete it as soon as Chapter 2 begins.
First Clue
If you want, you can visit the mines in Annesburg, as shown in the video. If you enter at the particular location we show you, you can enter undetected. Follow the video guide and you will find the first clue that there is some treasure to be found scribbled on a wall.
The Actual Sketched Map
The Sketched Map is located inside Reed Cottage, a small house found to the north of Annesburg and to the right of the "N" in Roanoke Ridge on the map. As the location's name is found on the map, it's very difficult to miss.
Once inside the cottage, check out the chimney on the left to find the map.
The Extra Clue
Finding this map is actually completely optional if you want to get the treasure, the first map you found above has enough detail to enable you to find the treasure without the second map/clue. But we are including it for completeness!
The second map/clue of the Sketched Map hunt is found near the northwestern ridge of Elysian Pool, right below the second "R" in Kamassa River on the map. In this area, you need to locate a tree with an "X" carved on it.
Once you have checked out the tree, you will find the second clue, which actually only indicates the direction you will have to go. Rotate your camera view accordingly, then head 20 steps to the north and five steps to the east. If you have done everything correctly, you will be at the location of the treasure and find a chest with a single Gold Ingot inside.
Gold Ingots can be sold to any fence for $300 each, so it's a nice profit for very little effort, especially if you're early in the story and don't have many ways to make money.