Spanish Romance is a standard in any classical guitarist's repertoire, and is based on a Spanish folksong. Spanish Romance is in two parts. The first section is in the key of Em, so it uses a lot of open strings. In fact, it is rather easy to play the first part. A melody is kept up front by using the ring finger right hand playing a solid rest stroke. A middle part is kept going by the index and middle on the 2nd and 3rd strings open, and a bass part is played with the thumb. Harmonically, it stays with 1 4 5 in em (em, am, B7) with a little secondary dominant at the end.
For most players, this section only starts to get hard when the bars come in. Without good technique, you will get too tense to keep the notes flowing with the right hand.
The second section is MUCH harder. Harmonically, it is interesting because it goes into the Parallel Major Key of E major. Because of this, all the left hand positions are a lot harder because you no longer have those nice open chords, due to G being sharp. I made it even hard for myself by putting in this little counter bassline I wanted to hear. I had to put in a lot of practice on those couple measures.
This piece is very accessible to people, they always love it, and probably no gigging classical guitarist could get along without it!