The overture In Nature's Realm, Op. 91, B. 168, was written by Antonín Dvořák in 1892. It is part of a "Nature, Life and Love" trilogy of overtures written by Dvořák, forming the first part - "Nature". The other two parts of the trilogy are the Carnival Overture, Op. 92 ("Life") and Othello, Op. 93 ("Love").
The overture is scored for two flutes, two oboes, english horn, two clarinets, bass clarinet, two bassoons, four horns, two trumpets, three trombones, tuba, timpani, triangle, cymbals and strings.