For this assignment I've mostly used images from sites that offer free licensing like Pixabay and Unsplash. All images used are found next.
https://pixabay.com/images/id-1680025/
https://pixabay.com/images/id-2445688/
https://unsplash.com/es/fotos/eZBmCd94cmE
https://unsplash.com/es/fotos/7fElVDKXLoQ
https://www.pexels.com/es-es/foto/arte-modelo-vintage-arquitectura-12258488/
https://pixabay.com/images/id-4517567/
https://pixabay.com/images/id-179150/
https://commons.wikimedia.org/wiki/File:Patio_de_Los_Leones_Alhambra_Granada.jpg
https://unsplash.com/es/fotos/qpTGte4bhv8
https://pixabay.com/images/id-326284/
https://pixabay.com/images/id-4262336/
https://unsplash.com/es/fotos/8e8agIS_xxE
https://unsplash.com/es/fotos/9doBGe7_hfA
https://unsplash.com/es/fotos/BObeW7-d6fk
https://commons.wikimedia.org/wiki/File:Spain_Andalusia_Granada_BW_2015-10-25_13-20-43.jpg
https://unsplash.com/es/fotos/N6tz-ocN1SI
https://elviajerofeliz.com/wp-content/uploads/2020/12/sierra-nevada-y-sus-encantos-0.jpg
https://www.dmproperties.com/cms/wp-content/uploads/2018/11/sierra-nevada-1636x1091.jpg
https://www.turgranada.es/en/fichas/national-and-natural-park-of-sierra-nevada-15198/
I've used 3 videos from YouTube, selecting different parts as mentioned below. Some of them were edited in the end result.
In total, their runtime in the final video is just below the 20sec/max requirement.
1:07 - 1:18
0:03 - 0:05
1:08 - 2:10 & 2:54 - 3:20
The fast tempo of the song makes it interesting to play with the synchronicity of the images and at the same time it reinforces them.