It had a fine history as a Roman fortress of sorts and in 889AD made into somewhat more formal fortifications. In 1333 Yusef started the project of remaking it into a palace and so it went.
Yusef seems to be an interesting person, at least by his Wiki article found here. He was stabbed to death in 1354 at the age of 36 while at prayer.
What brought on this little fishing expedition was a performance of a well know work for guitar "Memories of the Alhambra" by Francisco Tarrega. You will know it when you hear it (below). It was composed in nearby Granada 120 years ago or so.
We strongly associate guitar music, particularly of this nature, with Spain. The tradition, that particular sound and style, seems to me at least timeless, somewhat sentimental, and rich as one of the hillsides in the picture above as it basks in sun and color. I really like it and would love to see the Alhambra from a hillside, late in the day, with the air still and the sunlight just so.