These "10 Essential Challenging Works for Beginners" come in all different sizes, shapes, media, and styles. It's up to you to decide if you have the time and inclination to take them on--but you will be well-rewarded if you do. That much is certain. So be fearless. Take 'em on!

Handel: Giulio Cesare
Beethoven: Beethoven's Quartet No. 13 in B♭ major, Op. 130 (with Grosse Fuge finale)
Liszt: Fantasy and Fugue on the chorale "Ad nos, ad salutarem undam" (for organ)
Wagner: Tristan und Isolde
Mahler: Symphony No. 6
Sibelius: Symphony No. 4
Bruckner: Symphony No. 8
Bartók: String Quartet No. 4
Schoenberg: Pierrot Lunaire
Messiaen: Turangalila-Symphonie