“Originally this race was run over the memorable six-furlong straight course at Morris Park, then the newest and most elaborate of Metropolitan racing plants—which was a bit down grade and for that reason nicknamed the “toboggan slide”. (sic) (Hervey)
As racing historian John Hervey notes above, the name of the Toboggan has nothing to do with winter sports. For most of its life, the Toboggan was run on a circuit without winter racing, and it got its name from the slope of the course over which it was run at Morris Park in what was then Westchester County, now the Bronx. From 1890 to 1896, the race was called the Toboggan Slide.
The Morris Park Racecourse opened in 1889, the creation of John Morris and Leonard Jerome, whose own namesake track in the Bronx would shortly be closed. The topography of the landscape proved challenging in the track’s construction, but would serve to give the course its distinctive slope:
…the expense that would have been incurred in removing a solid table of rock prevented the obliteration of that “hill” in the course which has aroused so much criticism. As it is, this inequality of ground involves an ascent which has been facetiously dubbed “the Matterhorn,” and a descent in the main course…The hill again crops up in the Eclipse course, which is a straight six furlongs, or, if not exactly straight, having so slight an elbow in it that no horse can gain any material advantage through its existence. But in this case the inequality of the ground is entirely in favor of the horses, presenting a considerable decline. This, of course, accounts to a great extent for the many phenomenally fast times which have been made here. (Trevelyan)