I think this answers your question. Theater in New York moved from downtown gradually to midtown beginning around 1850, seeking less expensive real estate prices. In 1870, the heart of Broadway was in Union Square, and by the end of the century, many theaters were near Madison Square. Theaters did not arrive in the Times Square area until the early 1900s, and the Broadway theaters did not consolidate there until a large number of theaters were built around the square in the 1920s and 1930s. Broadway's first "long-run" musical was a 50-performance hit called The Elves in 1857. New York runs continued to lag far behind those in London,[8] but Laura Keene's "musical burletta" Seven Sisters (1860) shattered previous New York records with a run of 253 performances. It was at a performance by Keene's troupe of Our American Cousin in Washington, D.C. that Abraham Lincoln was shot. The Black Crook (1866), considered by some historians to be the first musical[9]The first theater piece that conforms to the modern conception of a musical, adding dance and original music that helped to tell the story, is considered to be The Black Crook, which premiered in New York on September 12, 1866. The production was a staggering five-and-a-half hours long, but despite its length, it ran for a record-breaking 474 performances. The same year, The Black Domino/Between You, Me and the Post was the first show to call itself a "musical comedy."[9] Tony Pastor opened the first vaudeville theater one block east of Union Square in 1881, where Lillian Russell performed. Comedians Edward Harrigan and Tony Hart produced and starred in musicals on Broadway between 1878 (The Mulligan Guard Picnic) and 1885, with book and lyrics by Harrigan and music by his father-in-law David Braham. These musical comedies featured characters and situations taken from the everyday life of New York's lower classes and represented a significant step forward from vaudeville and burlesque, towards a more literate form. They starred high quality singers (Lillian Russell, Vivienne Segal, and Fay Templeton) instead of the women of questionable repute who had starred in earlier musical forms. As transportation improved, poverty in New York diminished, and street lighting made for safer travel at night, the number of potential patrons for the growing number of theaters increased enormously. Plays could run longer and still draw in the audiences, leading to better profits and improved production values. As in England, during the latter half of the century the theater began to be cleaned up, with less prostitution hindering the attendance of the theater by women. Gilbert and Sullivan's family-friendly comic opera hits, beginning with H.M.S. Pinafore in 1878, were imported to New York (by the authors and also in numerous pirated productions). They were imitated in New York by American productions such as Reginald Dekoven's Robin Hood (1891) and John Philip Sousa's El Capitan (1896), along with operas, ballets and other British and European hits.