One of the biggest challenges during the construction of the Alaska Pipeline was when workers reached Thompson Pass. There, welders and laborers had to scale a near-vertical 2800-foot mountain wall to install pipe. The solution was to develop a tower and cable system that would fly the 80-foot pipe sections into place. On December 6, 1976, the last piece of pipe was laid at Thompson Pass.

The oilmen planned to build the Alaska pipeline the same way they'd built every other pipeline in the world -- dig a ditch and bury it. This would not work in the arctic. Beneath a thin, insulating cover of tundra and vegetation, much of Alaska sits on permanently frozen ground called permafrost. In some places, it's mostly gravel, but in others it's mostly ice.

On April 29, 1974, construction began on a haul road that would link the Yukon River to Prudhoe Bay. Truckers would use the road throughout the construction of the pipeline to transport goods to the North Slope as well as to camps along the way. By fall, the 360-mile long road was ready and would be used to haul three million tons of pipe, machinery, spare parts, fuel and food for 2 1/2 years.

Construction of the Alaska Pipeline began on March 27, 1975. Over the next three years, workers would battle brutal Arctic weather to construct an eight hundred mile pipeline that traversed three mountain ranges, thirty-four rivers, and eight hundred streams.

The massive scale of the Alaska Pipeline project made it difficult to maintain adequate supplies of equipment, electricity, and housing. Oil companies would spend almost any amount of money just to transport needed materials to the construction site. The one thing that was not in short supply was workers hoping to cash in on the project.

In the winter of 1976, Alaska Pipeline construction workers faced the daunting task of laying pipe at Atigun Pass, the highest point on the line rising at 4,800 feet above sea level. Additionally, the arctic weather made for extremely difficult working conditions. Due to the threat of avalanches at Atigun Pass, the pipe had to be buried beneath the permafrost soil.

In July 1975, Alyeska suffered its first scandal. A subcontractor was found cutting corners by falsifying weld x-rays. Thirty thousand eight hundred welds were in question. The x-rays were used to inspect all of the girth welds around the pipe's circumference. It would take Alyeska a year to check all the x-rays and to repair the sub-par welds.

As much as the Corps' officers wanted to punch the Alaskan Highway through in a hurry, dealing with muskeg (swamps of decaying vegetation) and mud drastically slowed things down. By the end of June after three months of work, the Engineers had constructed 360 miles of road. The Army knew it had about four months left to build at least 1,100 more miles before winter arrived.

At 4pm on October 25, the U.S. Army Corps of Engineers closed the last gap of the highway. In fewer than eight months, seven regiments had worked to their utmost limits to clear and lay down an astonishing 1,500 miles of highway. The men who built the highway overcame environmental, technological and physical hardships to complete what many consider one of America's greatest construction projects.

Stretching 1,500 miles through the sub-arctic wilderness, the Alaskan Highway was built to defend Americans from threats in the Pacific. The monumental job was assigned to the Army Corps of Engineers. The order was deceptively simple: build a road to Alaska as fast as possible. The Corps rushed over 10,000 men and 250,000 tons of equipment, materials, and supplies north on troop trains.

To clear a path for the road, a lead bulldozer, flanked by two others, tore into the dirt and knocked down trees to create a 60 to 90-foot swath. Behind these front units, the bulk of the regiment widened, straightened, and graded the road, and using the timber at hand, built culverts and bridges.

By September of 1942, the Army Corps of Engineers building the Alaska Highway had struck permafrost—ground that had been frozen for two or more years. After removing the covering vegetation, the frozen ground began to thaw, creating mud. Permafrost wasn’t the only challenge the engineers faced. In October, temperatures began to drop, signaling the start of one of the coldest winters on record.

In 1959, Fidel Castro created the Cuban Institute of Cinematographic Art and Culture (Spanish acronym: I.C.A.I.C.), the agency in charge of film production and distribution. The institute owned and controlled cinemas, oversaw all Cuban film productions and monitored imported films. View an excerpt from an I.C.A.I.C. newsreel of Castro's visit to the U.S.S.R. in 1972.

In 1959, Fidel Castro created the Cuban Institute of Cinematographic Art and Culture (Spanish acronym: I.C.A.I.C.), the agency in charge of film production and distribution. The institute owned and controlled cinemas, oversaw all Cuban film productions and monitored imported films. View an excerpt from an I.C.A.I.C. newsreel on the queue of asylum-seekers in 1980.

In May of 1942, across the rugged sub-Arctic wilderness of Alaska, British Columbia, and Yukon Territory, thousands of American soldiers began one of the biggest and most difficult construction projects ever undertaken -- the building of the Alaska Highway.

Historian Mike Wallace discusses the US and global interests, Lower West Side business, and the opposition to building the World Trade Center.

Writer Pete Hamill talks about New York before the World Trade Center, the New York economy, what was destroyed to build the towers, and getting used to the World Trade Center.

How did they do it? Find out in this eighteen-minute film, Building the World Trade Center, produced by the Port Authority of New York and New Jersey in 1983 with original footage of the towers under construction.

Architecture critic Ada Louise Huxtable discusses the options for building at Ground Zero and speaking to the spirit of the location.

Former New York governor Mario Cuomo talks about lessons learned from 9/11 and evolving toward a new civility.