During the 23 December 1998 flyby of asteroid 433 Eros, the Near-Earth Asteroid Rendezvous (NEAR) spacecraft obtained 222 images of Eros, as well as supporting spectral observations. The images cover slightly more than two-thirds of Eros (best resolution is approximately 400 meters per pixel) and reveal an elongated, cratered body with a linear feature extending for at least 20 kilometers. Our observations show that Eros has dimensions of 33 x 13 x 13 kilometers. The volume, combined with the mass determined by the NEAR radio science experiment, leads to a density of 2.5 +/- 0.8 grams per cubic centimeter. This relatively high density, and the presence of an extensive linear feature, suggest that Eros may be a structurally coherent body.