Creating a 3d Model for a Ski Hill in Aspen using QGIS

Introduction and Purpose

The purpose of this tutorial is to demonstrate how QGIS can be used to create a 3d model, and to demonstrate how to effectively create a model that will best represent what the user is trying to achieve. This tutorial will show how creating 3d models can be more effective for a map than a 2d map for certain situations. This tutorial will use the example of creating a map of a ski hill in Aspen. It will have the ski routes, gondola routes and key points that will be important for the map. This tutorial is meant for users who are brand new to 3d modeling, but also relatively experienced with QGIS and its main functions.

Downloading Imagery from Earth Explorer

To start, in order to create a 3d model we need elevation data. This is because without elevation data there is no 3d model. For this tutorial, we are going to be creating a 3d model of a ski hill in Aspen so in order to get this data you have to first find Aspen on the map. Next, once you find Aspen, create a study area using the "Polygon" feature found by scrolling down. Now you can either input manual coordinates or click "Use Map" and manually select the points for your polygon. Once this is done, on the bottom of the page select "Data Sets". For this tutorial, I used a Landsat Imagery DEM. You can select whichever Landsat dataset looks the best to you. Once you have your imagery selected, select "Results" and search for the proper imagery related to your area. You can do this by clicking on the foot looking button next to each selection. This will show a polygon of each DEM image. Once you find one that surrounds an Aspen ski hill you can download the imagery.

Creating your Study Area

Once the data is downloaded, you can now input the dataset to QGIS. As you can see, this image will most likely be fairly large. You have to clip this image to just a ski mountain in Aspen, not include other areas. In order to do this, we first need a base map so that we can see the ski mountains in the area. First, download the QuickMapServices plugin on QGIS. Once this is downloaded, it should show an icon of a little earth with a search bar on it in the Data Source Manager Toolbar. Now select the "Search QMS" option and then add the Google Satellite Hybrid base map. This will show Google Earth with Google Maps as well so you can find your ski mountain. Once you find a proper ski hill, first make sure it is within the DEM image. Once this is confirmed, create a polygon layer around the ski hill. After the polygon is created Use the "Clip" tool to clip the DEM to the polygon that you created so that the DEM is only the size of the ski hill. This will create your study area for the 3d Model.

Creating your Map

Once you have your study area, it is important to start georeferencing your lines and points for your 3d model. This can be done on the normal page of QGIS by creating line and point layers. In order to properly georeference the lines for the ski routes and gondala routes, make sure to use the Google Satellite Hybrid base map. This basemap includes the routes you need to add to the 3d Model. Once you have all these routes completed, make sure to change the size of the lines to what looks the best and input labels for these routes.

Creating your 3d Model

After georeferencing everything you need, you can now start to work on the 3d model. There are crucial steps that have to be taken in order to create a 3d model that looks good.

1.