Extreme Engineering

Season 1: 2003
(101) Tokyo's Sky City
(102) Subways In America / East Side Tunnel
(103) Transatlantic Tunnel
(104) City in a Pyramid / The Shimizu Mega-City Pyramid
(105) Bridging the Bering Strait / The Bering Strait Bridge
(106) Tunneling Under the Alps / Gotthard Base Tunnel
(107) Building Hong Kong's Airport / Hong Kong International Airport
(108) Holland's Barriers to the Sea / Maeslantkering and Oosterscheldekering storm surge barriers
(109) Boston's Big Dig
(110) Widening the Panama Canal / Panama Canal expansion project

Season 2: 2004
9 episodes were produced for season 2. It is also the first season produced in HDTV.
(201) Turning Torso / Turning Torso
(202) Venice Flood Gates / Venice Tide Barrier Project (MOSE Project)
(203) Container Ships / Adrian Mærsk (Maersk Line)
(204) Oakland Bay Bridge / San Francisco-Oakland Bay Bridge
(205) Iceland Tunnels / Kárahnjúkar Hydropower Project
(206) Oil Rigs / Jack up oil rigs in Louisiana
(207) Cooper River Bridge / Cooper River Bridge
(208) Millau Viaduct / Millau Viaduct
(209) Excavators / Hull-Rust-Mahoning Open Pit Iron Mine

Season 3: 2005
WagTV produced 6 episodes that were acquired by Discovery for season 3.
(301)The Snøhvit Arctic Gas Processing Platform / Snøhvit platform / MV Blue Marlin
(302)The El Cajon Dam / El Cajon Dam (Mexico)
(303)Hong Kong's Cable Car / Ngong Ping 360
(304)Woodrow Wilson Bridge / Woodrow Wilson Bridge
(305)Gotthard Tunnel / Gotthard Base Tunnel
(306)Dubai's Ski Resort / Ski Dubai

Season 4: 2006
Powderhouse Productions produced 6 episodes for season 4 with host Danny Forster. It currently airs under the Build It Bigger name on Discovery HD Theater.
(401) SuperStadium / University of Phoenix Stadium
(402) MegaTunnel / Storm Management And Road Tunnel (SMART) in Kuala Lumpur, Malaysia
(403) Biggest Warship / USS George H. W. Bush (CVN-77)
(404) Sakhalin Oil & Ice / Sakhalin-II
(405) Big Easy Rebuild / Reconstruction of New Orleans
(406) Space Tower / Madrid's Torre Espacio

Season 5: 2006
(501) South Ferry Subway Station / The New York City Subway's new South Ferry station
(502) World's Biggest Arch Bridge / Hoover Dam Bypass
(503) JFK: JetBlue Terminal / Reconstruction of John F. Kennedy International Airport's Terminal 5
(504) Stonecutters Bridge: Hong Kong / Hong Kong's Stonecutters Bridge
(505) California Academy of Sciences / The rebuilding of the California Academy of Sciences in San Francisco, California
(506) Hallandsås Ridge Tunnel: Sweden / Sweden's Hallandsas railway tunnel

Season 6: 2007
(601) Building a Destroyer / Portsmouth Naval Shipyard in Maine
(602) Fault Zone Tunnel / Freshwater pipeline to support Southern California. Watch a TBM at work.
(603) Boot Camp / With Excavators in Boston, Massachusetts.
(604) World's Tallest Skyscraper / Shanghai World Financial Centre
(605) Battle Machines / To see how a M1 Abrams tank beeing maintenanced in Fort Knox, Kentucky
(606) Coaster Build Off / Griffon a steel rollercoaster in Busch Gardens Europe and the Renegade in Valleyfair
(607) High Risk Tower / City of Culture of Galicia