How to Plot UTM Points

Plotting UTM points onto an adventure race map is typically a skill reserved for “longer” races. It often shows up in expedition races, where you’ll plot UTM points either pre-race when mapsets are received, or on-the-clock when more of the course is revealed during the actual race.

That’s not to say you won’t see it for certain 12 hour or 24 hour races, depending on the old-schoolness of the Race Director. Plotting your map used to be the norm. It was one of the basic required skills in the navigation bucket. 

The good news is, that you should be given a heads up if you’ll need to plot points. If it’s not explicitly stated, a great tipoff is the inclusion of a UTM Plotter listed on the mandatory gear list. Another tell is if you see mention of a pre-plotted map – this simply means that checkpoints are already printed on the map for you.

So, if you need to brush up on your plotting skills (or learn completely from scratch) here’s how to plot UTM points for adventure races

5 steps to plot UTM points for adventure races

First things first, you’ll need a UTM Plotter. Most ARs require a 1:24,000 scale plotter (this is the scale you’ll be using for most maps that need plotting). There’re two styles, Slot and Corner. Both work well, it’s just personal preference; some find the slot style a little quicker.

With plotter in hand, you’re going to receive your race map(s). These maps will have a UTM grid overlaid on them with each square equaling 1 kilometer. Along the edges, you’ll see the actual UTM coordinates for each easting line (the lines running up & down along the Y axis) and each northing line (the lines running left to right along the X axis). So, here are examples of both the Race Map and UTM Coordinates you’ll receive. Let’s try plotting the Start/Finish to a 24 hour race we hosted in Kentucky.

UTM coordinates
UTM grid squares

Look at all those numbers! Don’t worry, you only need a few. When we race, our team actually crosses out the extraneous digits on the UTM Sheet, so there’s no confusion. Sometimes the Race Director will do this for you, providing a simplified version. Also note that the digits to start with are actually larger in the image of the coordinates above (09 and 79) making it even easier to know which ones to start with. Now we’re ready to plot this point on the actual map.

identifying the correct grid square associated with an UTM coordinate

UTM 16S 04 09064E 40 79417N

STEP 1: just find the grid square the point is in.

using a UTM plotter to plot a UTM coordinate

Overlay the plotter tool

STEP 2: put the upper right corner of your plotter tool on the lower left corner of the correct grid square (just make sure you’re using the right scale on your tool, 1:24,000).

using a UTM plotter to plot a UTM coordinate

UTM 16S 04 09064E 40 79417N

STEP 3: slide the plotter right until you reach the correct easting. This one is 06, so it’s just 60 meters off of the line. 64 meters if you want to get really precise, but for our purposes, not trying to plot with that level of accuracy is precise enough for this scale map.

marking a checkpoint using a UTM plotter to plot a UTM coordinate

UTM 16S 04 09064E 40 79417N

STEP 4: slide the plotter up until you reach the correct northing. This one is 41.

STEP 5: mark the checkpoint! Now you know where the start of the race is and more importantly how to plot UTM points onto an adventure race map – always helpful.

Pro Tips for plotting UTM points quickly and accurately

Using the Slot style tool saves you the step of moving the tool up for the northing, you simply mark it through the slot.

If you have a teammate, it works very well for one person to read the digits to the person plotting. For the example above, “grid square 09, 79” gets them in the right square. “06,41” lets them plot the point. We like to have the person plotting guess the feature to verify it’s correctly placed, “hilltop”…”yep”.

The more races you do, the more formats you’ll see UTMs written in. For the example above, it could be written as 409064,4079417 (zone and leading zero removed). A typical format for adventure races would be 409060E,4079410N (leading zero removed and last digit truncated). Regardless, plotting remains the same.

Mark Lattanzi nails it perfectly in his book Squiggly Lines. This is pretty much the bible of navigation for AR, so check it out if you don’t already have it. If you do have it, flip to page 30, read three pages, and you’ll be a near-expert.

Written by

Shawn Lemaster