The tutorial provides a comprehensive guide on using interpolation in QGIS for creating complex surface layers with contours.

It covers the process of finding elevation data, loading point datasets into QGIS, selecting an interpolation method, creating a surface layer, and checking the accuracy and completeness of the output layer.

The tutorial also explains how to convert a raster elevation layer to contours in QGIS and create a surface layer using the “Grid (Nearest Neighbor)” tool.