Piano Sonata no. 29 in B flat major, op. 106, "Hammerklavier"

The Piano Sonata No. 29 in B♭ major, Op. 106 (known as the Große Sonate für das Hammerklavier, or more simply as the Hammerklavier) by Ludwig van Beethoven was composed in 1817 and published in 1818. The sonata is widely viewed as one of the most important works of the composer's third period and a pivotal work between his third and late period. It is also considered to be Beethoven's most technically challenging piano composition and one of the most demanding solo works in the classical piano repertoire. The first documented public performance was in 1836 by Franz Liszt in the Salle Érard in Paris to an enthusiastic review by Hector Berlioz.