This is a famously beautiful arrangement of a Catalan folk song, by Romantic Era guitarist/composer Miguel Llobet. He wrote/arranged a set of 13 such songs, and this is probably the most famous one, frequently played as an encore.
Miguel Llobet, who always looks serious: 1878-1938
One of the most lovely special touches in this piece is the use of harmonics for the echo-like repeat of the melody, which happens twice. In the video, This takes some practice! I gave you a close-up view of the right hand while it plays the harmonics section.
Enough with the serious face. This is somewhere beautiful in Catalonia.
Enjoy!