The Mars Yard, which is officially unveiled by the Business Secretary Vince Cable today, creates a realistic Martian environment in which to test the prototype rovers.
It contains 300 tonnes of selected sand and the geographic conditions which best match the environment of the red planet.
The sand colour and composition has been selected to match the Martian terrain and the light levels are set at 2000 lux, which has a colour content which mimics the conditions on Mars.
The development phase will be complete by the end of this year and the contraction of the launch of the Mars rover is scheduled for 2018.
Engineers in Stevenage will start construction of the flight rover in 2015 after the three prototypes - Bridget, Bruno and Bryan - have been evaluated in the Mars Yard.