It was difficult because of the harsh weather conditions and because of geography. Since it was really bad snow then the workers had to work harder. Geography because of the mountains they had to make holes in the mountains to let the train go through but they had to make sure it would not caluple.
they faced many land obstacles, very little pay, and long hours.
The threat of the Native Americans.The Native Americans felt upset about being pushed out of their own land. They didn't believe in land ownership. So when people came looking for places to set their tracks, the Native Americans came and scalped them, burned them, or killed them.
Harriet Tubman's biggest obstacle was discovering the Underground Railroad. She became famous by finding the Underground Railroad, that led to the north. She freed over 300 slaves.
The Sierra Nevada mountains.
the mountains
Mines
A railroad would make it possible to travel the distance to the Pacific much faster and much more easily.
war and the disagreements of citizens vs, power
The mountains proved to be a formidable obstacle in the building of the railway, proving costly in delayed time and soaring construction costs.
I guess you mean skyscraper. The initial obstacle to building such a tall building would be the softness of the terrain, as most of Mexico City downtown lies on the desiccated remains of Lake Texcoco. Nowadays, most tall buildings (+20 stories and more) are built on the periphery of the city, on financial districts such as eastern Reforma Avenue, Santa Fe and Colonia Del Valle.
obstacle of reading