The closest Republic quick travel point is the Ken-La Outpost quick travel point and the closest taxi is the Ken-La Outpost speeder point, both west, before pilgrim's retreat.
The closest Imperial quick travel point is the Fort Kodentha quick travel point and the closest taxi is the Fort Kodentha speeder point, both southwest between skyline and pilgrims retreat.
Voss Mastery +4 Datacron (Both Factions)
Quicktravel: 
Taxi: 
Location: Old Paths - cave accessed by climbing a hill with some rocks in the southeast
Difficulty: Medium - some jumping, easy to retry
Codex: Galactic History 77: A Return to the Unknown RegionsYou can see this purple Datacron while traveling on the Voss speeder, but you’ll need to find the secret path that starts far away to get to it. There is no way to stop or pause the taxi.
You may also see it while exploring the capital city of Voss-Ka, and be tempted to jump down to it. If you do, even if you are a careful rock jumper, you will automatically die once you get to a certain point down the mountains, so you’ll need to find another path to reach the purple datacron.
Quick Travel / Taxi
Find the Hill
Follow the Rock Path
At one point the path looks like a dead end, back track a bit and start jumping up again.
Jump Up the Rocks
Eventually you will reach the broken circle of columns with the datacron.
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