 Mendelssohn's mature symphonies are numbered approximately in the order that they were published, rather than the order in which they were composed. The order of actual composition is: 1, 5, 4, 2, 3. The placement of No. 3 in this sequence is problematic because he worked on it for over a decade, starting sketches for it soon after beginning work on No. 5, but completing it after both Nos. 5 and 4.
