Install QGIS on Ubuntu

QGIS is an open source program which allows you to: "edit, visualise, analyse and publish geospatial information on Windows, Mac, Linux, BSD and mobile devices. For your desktop, server, in your web browser and as developer libraries."

To install QGIS 3.10 (Long Term Release, A Coruña LTR) on Ubuntu 18.04 (bionic) or Ubuntu 20.04 (focal) follow this guide:

NOTE: Follow the guide, but under "Add the QGIS repo ...". It will install the Latest Release, so to get the Long Time Release, you have to manually define the repo version.

https://qgis.org/en/site/forusers/alldownloads.html#debian-ubuntu

# DON'T DO THIS:
sudo add-apt-repository "deb https://qgis.org/debian `lsb_release -c -s` main"

In stead, edit the sources file directly. If you have Sublime Text installed, you can open the file with this command:

subl /etc/apt/sources.list

Add this at the bottom to allow access for the QGIS repository Ubuntu, and save:

deb     https://qgis.org/ubuntu-ltr bionic main
deb-src https://qgis.org/ubuntu-ltr bionic main

For Ubuntu 20.04, insert this in stead:

deb     https://qgis.org/ubuntu-ltr focal main
deb-src https://qgis.org/ubuntu-ltr focal main

Continue with sudo apt update, etc.

The QGIS training manual is a great introduction. Also, some videos based on the manual exist, though it seems like some steps are missing here and there: GIS 101: a complete tutorial for QGIS3.

Training Data: https://github.com/qgis/QGIS-Training-Data