Answer:
If you travelled due west from Denver to San Francisco you will witness beautiful views of American West. While leaving Denver you will see beautiful tall and Rocky Mountains.
Travelling west will witness you all type of vegetation like the green grassland, deserts, mountains and plain areas. Nevada is also on the way to San Francisco from Denver. It is the driest dessert.
Central Valley of California can also be seen during the travel which is the most agricultural areas around the globe.