Displaying two different layers in the same coordinate systems in QGIS

Question

This looks like an easy solution but, for the life of me, I cannot manage to solve this. I have browsed this website where solutions were provided but unfortunately, none have produced the desired outcome.

I am very novice in QGIS, so any solution provided should be very detailed.

I have downloaded layers that contain information on the type of land cover (source: source of CLC layer). After importing in in QGIS (New Project>Browser>GeoPackage>New Connection>path to file) and then dropping the file in the Layers, I see the layer and its contents. At the bottom right, the CRS is EPSG:25830. In the Properties of the layer (right-click on the layer and click on Properties), I see that the CRS is EPSG:25830. (see the properties of the land cover layer: and its assigned CRS: )

Now I want to overlay the limits of the municipalities. The SHP file comes from here. To check its coordinate system, I uploaded it to MyGeoCloud. Its reference system is WGS 84 / Pseudo-Mercator (EPSG:3857). If I import it into a new QGIS project, it displays that value too.

I have tried this:

1. Import the land cover layer into a new project, then drop the municipalities => failed

2. Import the municipalities and then the land cover => failed

   However, I was under the impression that QGIS (I am using 3.36 Maiden) was able to adjust that.

3. Reproject the shapefile before importing to the project => failed.

   Some answers here suggested reprojecting the layer (I will reproject the municipalities layer). So I did: New Project>Import the limits>Vector>Data Management Tools>Reproject Layer. I chose EPSG: 25830 as the Target CRS. I then export the layer by right-clicking on the layer>Export>Save Features As...> and I choose a name for that file. If I right-click on that exported layer, I see that the CRS of that layer is the one I want:

   

I create a new project and drop the new shapefile with the CRS of 25830 and the CRS I want is at the bottom-right of QGIS.

I drop the layer of land cover onto that project and it does not match. .

What do I do wrong? Could you list a workflow that would work?

EDIT: steps to download the layers: Land cover layer:

1. Go to this link and search ("Buscar") ,
2. then download the Geopackage file.

SHP file of the municipalities:

1. Go to this website (or search "municipios ign esri" on Google if the link does not work)
2. Download as SHP

Answer 1

The problem seems to be a CRS issue: you probably (wrongly) changed the layer's CRS what you should never do if you're not really 100% sure what you do: see here for details. Whenever a layer does not fit on a basemap, in about 99% it's becaus a wrong CRS definition was assigned to it.

So to solve the problem:

1. Create a new, empty QGIS project with an OSM basemap and drag and drop your files. They should perfectly allign with the basemap. I always recommend this to see if the data is located in the correct location:

   

2. As your files come in two differen CRS (see here and here), for intersecting them, you should reproject them to the same CRS. I would advice to reproject Municipios layer from EPSG:3857 to EPSG:25828 as the other layer. Go to Menu Processing -> Toolbox -> Reproject Layer.

   Alternatively, right click the layer -> Export -> save featuers as... and there, choose the CRS you want to reproject to. This has the advantage that you can also save the file as a Geopackage and avoid the cumbersome handling of Shapefiles.

3. Another problem with your data appears when you want to Intersect: Feature (522) from “Municipios_IGN” has invalid geometry. Run Fix Geometries to repair them, then Intersection works.