On Sunday, October 1, at 3 p.m., the Boston Symphony Orchestra and the Boston Pops, in partnership with the City of Boston, will present a special free concert in Boston's Franklin Park.

Franz Joseph Haydn and Gustav Mahler defined the genre of the symphony during their respective eras- Haydn as one of its originators in the late 18th-century Classical era, and Mahler as revitalizer and innovator at the end of the Romantic era.

To begin the program, English pianist Paul Lewis is soloist in Beethoven's lyrical and poetic Piano Concerto No. 4, which famously opens with a disarmingly intimate passage for solo piano.