For free pictures I guess one could use:

 

   https://unsplash.com/about

   https://www.pexels.com

 

If you check there for "lighthouse" you will find nice ones like:

 - https://www.pexels.com/photo/gray-and-black-rock-formation-1113552/

 - https://images.unsplash.com/photo-1556290287-14de2be0657b?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=500&q=60

 

You can even get the "spiral" effect there:

 

 https://unsplash.com/s/photos/spiral

 https://www.pexels.com/search/spiral/