Dive More than 60m in Single Player

Far Cry 3 Walkthrough - Dive More than 60m in Single Player

Swim out far into the ocean. Use the map to make sure you're not swimming into shark-infested waters. Then use the "Deep Dive" syringe. This syringe can be crafted using 2 Blue Leafs and 1 Green Leafs. You'll have to do work before unlocking this syringe, such as finding relics, but it is earned fairly early on and is under the "Exploration" category.

Dive More than 60 Meter

After you have used this syringe, dive straight down into the water. Keep swimming straight down until the achievement pops up. Click on the left analog stick to make Jason swim faster.