Civil engineering programs prepare people to plan, design, and construct large structures and systems such as subways, tunnels, and bridges. Students learn to use math and science to solve real-life problems. They also learn about urban planning.
Long ago, engineers were people who constructed military "engines." They built siege towers, battering rams, and catapults. They also constructed the defenses - castle walls and moats. Then, people started using those same skills for civilian purposes. They built bridges, roads, and tunnels for peacetime - hence the term "civil (for civilian) engineer."
In a civil engineering program, you study a lot of math and science. You especially study mechanics - how a body will move, or how forces will be distributed in a body at rest, according to the laws of physics. You see how these principles apply to soil, water, rock, and components of structures. In doing so, you learn how to solve problems related to construction projects. You learn to consider economic matters as well, since public-works projects rarely have unlimited budgets.
A bachelor's degree is good preparation for a career in this field. Normally you can earn one with four, perhaps five years of full-time study beyond high school. A large number of colleges in the U.S. offer this program. In some programs you can progress straight through to complete a master's in five years.
In addition, traditional master's and doctorate degrees are offered in this field. In general, master's degrees take two years to complete, and doctorate degrees take another three to five.