Prior to the building of Bartow Station, a stagecoach service operated by Robert Vickery ran between Mount Vernon and City Island.

The lead car overturned on a sharp curve approaching the City Island Bridge, resulting in many injuries, some of them severe.

[6] The same year, City Island resident Richard S. Williams filed a complaint with the Board of State Railroad Commissioners that the two companies were unlawfully double-charging passengers.

Residents of the surrounding area opposed the franchise because a new rail line on that route would require tearing up Shore Road's pavement.

[11] On December 8, the New York Supreme Court placed an injunction to prevent the franchise from being sold to the Pelham Bay Railroad.

[22] In October 1908, application was made to the New York State Public Service Commission to change the motive power of the railroad from horse to overhead electric current.

Howard Tunis, who was operating the vehicle, received a broken rib, and his 6 year old daughter Eugenia suffered bruises.

In 1913, the IRT decided to convert the line to a 4 ft 8+1⁄2 in (1,435 mm) standard gauge electric trolley system and with this in mind, merged the two companies into a new entity, the Pelham Park and City Island Railroad, which took over operation on July 1, 1913.

The trackage across the bridge and on City Island was converted to standard gauge, with leased New York Railways horsecars taking over the service.

[33][34] After taking control on August 1, 1914, the Third Avenue quickly completed construction of the standard gauge railway, but did not install overhead wire.

The first storage battery car began operation from Bartow to the line's end on City Island at 12:30 p.m. that same day.

[35][36] In 1919, the Third Avenue Railway petitioned the New York Public Service Commission to permit abandonment, on the grounds of insufficient funds to continue operation; the PSC granted the permission.

[38] On August 11, New York City mayor John Francis Hylan also wrote to the commission, noting that the railway had been losing almost $18,000 (equivalent to $320,000 in 2023) per year and that he was opposed to continuing to run the railroad as a municipally owned service.

Hylan suggested that the equipment be sold to "people who deal in second-hand railroad scrap, who are commonly called junk dealers".