S6 E1 • Tunnel Vision

Return to the 57-kilometer long high-speed rail tunnel in Switzerland's Gotthard Mountain range to see what it will take to finish the project by 2017.

S6 E2 • Extreme Surf Machine

Returning to Tenerife to check on the world's best water park which now seems destined to remain dry after numerous problems.

S6 E3 • Race to the Games

Crews race against the clock to finish an important venue and signature landmark for the 2012 London Olympics.

S6 E4 • Tunneling Through History

Mega Builders return to Istanbul to update the Marmaray rapid-transit project, which continues to have delays.

S6 E5 • Quake-Proof Bridge

Examining design and construction of the San Francisco-Oakland Bay Bridge, designed to withstand an earthquake.

S6 E6 • Revisited

Mega Builders revisits previous covered projects and gives us an update to their progress