An intervertebral implant for fusing vertebrae is disclosed. The implant has a body with curved, substantially parallel posterior and anterior faces separated by two narrow implant ends, superior and inferior faces having a plurality of undulating surfaces for contacting upper and lower vertebral endplates, and at least one depression in the anterior or posterior face for engagement by an insertion tool, at least two vertical through-channels extending through the implant from the superior face to the inferior face, a chamfer on the superior and inferior surfaces at one of the narrow implant ends, and a beveled edge along a perimeter of the superior and inferior faces. The arcuate implant configuration and the chamfers on the superior and inferior faces at the narrow end facilitate insertion of the implant from a transforaminal approach into a symmetric position about the midline of the spine so that a single implant provides balanced support to the spinal column. The implant may include radiopaque markers extending through the thickness of the implant to indicate the location and size of the implant. The implant may be formed of a plurality of interconnecting bodies assembled to form a single unit. An implantation kit and method are also disclosed.