How long did it take to build the Mars rover?

Answer 1

Each component or (service module) on the rovers are built, manufactured, and assembled in a sterile and sometimes vacuum sealed environment.

Some assembly can be done in a matter of days, but even those "partial" assemblies will sit for an entire year (or longer) as other instruments are added for that particular assemblage on the rover.

To boldly answer your question: approximately 3 years.

Answer 2

It took approximately 6 years to design, build, and test the Mars rover. The engineering process involved a team of scientists and engineers working together to develop and construct the rover's complex systems, ensuring its successful mission on the red planet.