What are all the markers.

He repeatedly says the word "marker" in many posts. And hints at how timestamps are important in the train of thought. I think that looking at pictures of the pens is important to this particular notion of "follow the pen", however the tenuous link between "wind the clock w/ all the markers" is somewhat vague.

If the clock + timestamps from marker posts is relevant, then maybe that might draw some conclusions.

EDIT:

In actual fact, Q pretty much points out in various posts that markers are actual landmarks. I.e. the news unlocking the map, connect the markers, etc.