Here is the full list of all 14 Journey achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Start the journey again after a week long break.
Pass through 15 gates while surfing through the sunken city.
Cross the broken bridge without completely rebuilding it.
Uncover all 10 ancient glyphs.
Collect all unique glowing symbols across one or more journeys.
Discover all cloth creatures in the desert.
Meet 10 or more unique travelers.
Find the hidden desert flower.
Sneak through the underground passage without tearing your scarf.
Find a mysterious creature hidden in the temple.
Sit and meditate with another player for more than 20 seconds.
Reach the summit with a companion and return to the beginning.
Finish the game and return to the beginning.
Finish the game with the same partner for the majority of the journey and return to the beginning.