A bridge opened over the former Marble Hill alignment of the creek in 1900, carrying Broadway. The bridge's superstructure was demolished shortly afterward, with the construction of the IRT subway above Broadway in 1904. The effect of channeling through what had been 222nd and 223rd streets was to physically isolate Marble Hill on the Bronx side of the new strait. In 1914 the original creekbed was filled in with rock from the excavation of Grand Central Terminal's foundation during its construction; and the temporary island, comprising present-day Marble Hill, became physically attached to the Bronx, though it remained politically part of the borough of Manhattan, as it is today. The bridge carrying Broadway over the former alignment of the creek at 230th Street was destroyed in the late 1920s.