I would go for AF-S DX Zoom-Nikkor 12-24mm f/4G IF-ED, Tokina AF 11-16mm f/2.8 AT-X Pro DX, Sigma 10-20mm F4-5.6 EX DC HSM, Sigma 12-24mm f/4.5-5.6 EX DG IF HSM Aspherical. You need the wide for landscape. Sometimes you can see a distorsion which gives a fisheye look on certain wides :D