'Path to' indicates the way to get to something, the direction you would take to get to it. (eg the route you take to get to the top of a mountain)
Path to the iceberg
This would explain the route (or the steps) you take to get to the iceberg
This is sometimes also metaphorical (path to enlightenment/salvation)
The path to salvation requires you to do (x) before you can start upon it
"Path of" indicates where a particular something itself is going to or has been (like the trajectory of a planet)
Path of the iceberg
This tells you where the iceberg is going (or has been)
This could also be metaphorical, but would mean the direction you take to stay on the path of enlightenment/salvation
The path of enlightenment is fraught with temptation
As Jason says in comments - for metaphorical use, it might not matter which one is used.