Norbornene (NB) was oligomerized at 0 degrees C using AlEt2Cl-TiCl4 at a monomer/titanium molar ratio of about 11. The oligomerization product consists of a fraction soluble in diethyl ether, amorphous by X-ray examination, and of a crystalline fraction, insoluble in diethyl ether. The crystalline fraction was shown by powder X-ray diffraction to consist of a NB heptamer. Single-crystal X-ray analysis indicated that the heptamer had a stereoregular 2,3-exo-disyndiotactic structure. The heptamer adopts a strained, highly irregular, folded conformation in the crystalline state. Structural differences with respect to NB oligomers obtained with zirconocene catalysts are discussed.