Abstract: A cable tray comprising a tray supported on each side by a side rail. The tray includes a plurality of cross members combined by longitudinal members. The tray includes a bottom portion for supporting the cables and side walls on either side of the bottom portion to help retain the cables in the tray. The side rail is a generally solid body which supports the tray and is removably combined with the tray's side walls. The side rail includes a lower support and a web. The lower support includes a surface adapted to support a portion of the bottom portion of the tray. The web extends upwardly from the lower support and is spaced from a lip or retaining member forming a gap or opening between the web and the retaining member. The opening is adapted to receive a portion of the tray's side wall to help secure the tray to each side rail.