The International Space Station is the largest structureever built in space. Its backbone-like main truss is as long as a footballfield and the station can clearly be seen from Earth by the naked eye, sometimes rivaling the planet Venus in brightness. Today, the space station is home to crews of up tosix astronauts representing five different space agencies and 15 countries thatbuilt it. Construction on the $100 billion InternationalSpace Station began in 1998 and is expected to be completed by mid-2011. SPACE.com looks at the space station from the inside out to take a close look at orbiting lab.

<a href="/8897-graphic-international-space-station.html"><img src="http://www.space.com/images/iss-international-space-station-construction-history-100812a.jpg" alt="Learn how the International Space Station (ISS) was constructed and developed to provide a permanent base for astronauts to live and work in space" width="580" border="1"/></a><br /> Source Space.com: All about our solar system, outer space and exploration

This graphic has been corrected to reflect the proper orientation of the space station's Russian docking ports.