Why do I envision time at different geometric points? Probably due to subconscious memories of elementary school bulletin board displays, or textbook timeline charts. Some "chunks" of time are set apart with a greater focus on individual years, while others are a long line with nothing to distinguish them.
This is going to take some drawing, and I'm a lousy artist. Bear with me. I also don't want to mark specific events on the line, as it will become an exercise in "looking things up" that I remember imperfectly.
The B.C. years emerge from a misty patch to my right - they go back endlessly past some invisible horizon, but from about the time of Moses is when I can see the beginning of the line. They go in a straight line to the left, until 60 BC, when they break left and go straight down until the BC/AD turnover, where they resume their journey to the left. Upon reaching AD 30-ish, the line turns right and goes straight up through 300 AD, when it breaks left again and continues on in an unbroken line until the Renaissance.
In the year 1400, time begins to fold back and forth upon itself; still continuing from right to left, but starting in the year 01, going straight up to the year 00, and then turning left and skipping back to the starting point of 01, to repeat the upward journey until the year 1800.
In 1800 time takes the left turn, but instead of skipping back down to the 01 starting point, it takes a hairpin turn and time starts running the other direction, from top to bottom. At 1900, time turns right, and skips back up to the "top of the page" and starts running downwards. Only now the line becomes thicker, and as you follow it along, the individual years stand out, and each one has an actual visual significance. It's like zooming in on a DNA strand, and starting to see the details of each individual dot. You realize that each year within the line is actually an oval, which loops from top left down until June-July, and then loops back up on the right to make the oval. Look closer, and each month is, of course, a calendar page, a square grid strung one after the other like beads on a necklace.
Upon reaching 2000, the line becomes less certain - you can't quite figure out which direction it is going, or plans to go. Currently, it is still continuing on from right to left, but it has made no turns - it is the same unbent line since 1900. I suppose that because this is the part of the line that I am personally living in, I can't make it bend any direction other than the inevitable drive to the West/Left. Give me a few more years and maybe I will be able to see if it will bend.
I suppose psychological gender studies that look into this sort of thing might make much of the fact that individual years are circular (feminine), while the direction of centuries is in straight lines (masculine). Maybe because women instinctively count the months for their menstrual cycle, or the cycle of yearly rebirth and death is more apparent to women; and the straight lines of history are more about time as visualized by the men who made most of it. I have a healthy curiosity of gender differences, but ultimately all I can say is that my visualization of time has been the slow development of education, books, culture and my perception of the years I have actually inhabited time.
Now... it's your turn! How do you see time? I'd love to hear about it.