Étude Op. 10, No. 1 in C major is a study for solo piano composed by Frédéric Chopin in 1829. It was first published in 1833 in France, Germany, and England as the first piece of his Études Op. 10. This study in reach and arpeggios focuses on stretching the fingers of the right hand. Also referred to as the Waterfall Etude, Op.10, No.1 is considered one of the hardest of Chopin's 24 Etudes, ranking the highest level of difficulty according to the Henle difficulty rankings.