Monday, September 7, 2015

Making Maps

Although I have (over the years) run on more maps than I can count - with countless names written in the bottom corner as to who made those maps - I had never really considered the amount of work that goes into making a map so that I can use it.  That is, until I tried my hand at making one myself!

These past two years, I have been going to school at UWC Atlantic College, an international 6th form school in south Wales (UK) boasting over 100 languages, 90 countries and a myriad of ruins, formal gardens and beautiful 13th century buildings, but not one up-to-date orienteering map.  The most recent (and only) map I could find of the school grounds was from 1975, and featured 25 foot (or 7.6m) contours!  It was also hopelessly out of date for while the castle had changed very little, the grounds were very different and there were a number of new buildings.  The mapping standard for sprint maps has also changed considerably in the last couple decades.

The first thing which I did was acquire LiDAR data, which is invaluably useful as it gives you very precise contours.  Luckily, because I was making an orienteering map, I was able to get the data for free!  There are two kinds of LiDAR data: Digital Surface Modelling, which shows the underlying contours of the land, and Digital Terrain Modelling, which shows the land, as well as all the buildings, stone walls and big trees as very steep contours!  See if you can match up the map above with the DTM below!

Next came the task of actually drawing the map!  I first made a rough sketch of the map using the LiDAR and the old map, and then proceeded to walk all over campus, drawing in missing walls, staircases, trees and more.  Then it was back to the computer to add those bits in before heading out into the field again.  Bit by bit, the whole thing started to come together.

Things I learnt while mapping:

  1.  Forests are best mapped when there is no foliage at all, as otherwise you can barely see 10m in front of you
  2.  Areas where there are staircases, overpasses, fences and walls all on top of each other are almost impossible to get right
  3. Inevitably you are going to forget something and will realise just as you are getting ready to be finished (for the 10th time…)
  4. Someone will inevitably find said omission the second they pick up the map and look up
  5. It is completely worth it the second you see others enjoying themselves on your map
The next step was to run an orienteering activity using the map I had just made.  I decided to run it once a week focusing on a different aspect of orienteering each week.

One week, when it was very rainy, we played with play dough in an attempt to better understand contours.  I brought a number of my old maps in, and instructed my fellow students to choose a hill from the map and build it from play dough.  Then it was up to everyone else to guess which hill they had made!

Can you guess the hill?
Another week I created a labyrinth over the map and placed multiple controls on it.  It was a score O, but you were not allowed to cross any of the black lines (this is a very good exercise on a map you know inside-out, as it forces you to focus on the map).

How would you get from 48-32?
Of course, every training needs to include a race, and so as the last training we ran a course to see how much we had learnt.  All in all, it was (I hope) a great learning experience for my fellow students and it was most definitely a great learning experience for me.