Charles Carleton Coffin would be haunted by the sight for the rest of his life.

Behind the iron gate of the "MART," Coffin found a long hall lined with benches down one wall, a platform on the other and, beyond it, a four-story brick building with grated windows and iron doors.

He was standing in both a prison yard and an auction house.

Coffin, a reporter with the Boston Journal, was one of the first newspapermen to reach Charleston after the Confederate military abandoned it in February 1865. He immediately set out in search of the city's largest slave market so he could describe it for his readers in Massachusetts.

As Coffin stood looking at the auction block, he heard a voice behind him.

"I was sold there upon that table two years ago."

Her name was Dinah More, Coffin would later write, and she was one of the thousands of enslaved Africans who had passed through that gate as property.

The start of the Civil War 150 years ago this week marked the beginning of the end for the "peculiar institution" of slavery. In 1865, the 13th Amendment to the Constitution officially abolished slavery in the reconstructed United States, bringing great change to the country's culture and the South's economy.

By 1860, there were 4 million slaves in the United States, and 400,000 of them -- 10 percent -- lived in South Carolina. African-Americans, enslaved and free, made up 57 percent of the state's population. Charleston was the nation's capital of the slave trade, the place where many of those enslaved people first landed in the New World.

The city was built on slave labor and, for nearly 200 years, thrived under a slave economy.

Nearly a century and a half has passed since slavery was abolished, but the wounds still linger. Even in 1865, long after Charleston's slave mart had sold its last human being, the occasion was bittersweet. When Coffin told More that she was free, and would never be sold again, she was melancholy.

"O the blessed Jesus, He has heard my prayer," More said. "I am so glad; only I wish I could see my husband. He was sold at the same time into the country, and has gone I don't know where."

In the mid-19th century, it was an all-too-common story.

Ground zero

Any history of slavery in America begins with Charleston.

During the Transatlantic Slave Trade, about 40 percent of enslaved Africans brought into the country passed through Charleston Harbor. Often these slaves were sold around the South to supply the plantation industry with the cheap labor it needed to be profitable. But a great number of those slaves remained in South Carolina.

"This place is absolutely central to telling the story of slavery," said Bernard Powers, a professor of history at the College of Charleston. "I'm still amazed by how many people and their families are rooted here in South Carolina."

The lives of enslaved people varied greatly, especially in Charleston, and historians still disagree on many aspects of their experiences.

Some toiled in the same fields, day after day, year after year, the view never changing; others worked in the comfort of fine homes, with better food, clothing and living conditions, yet had to be on-call 24 hours a day, subject to the whims and moods of their owners.

Many slaves, interviewed by government writers in the 1930s, described brutal beatings for the smallest offense. Some were sexually abused by their owners; some young enslaved girls were bought at least in part with that in mind.

Others say they had "kindly masters."

But no matter their experience, they were all held in bondage.

Amid this shared experience, a new culture was born. In the Lowcountry of South Carolina and Georgia, the Gullah were people who clung to aspects of their African heritage, including their crafts and folktales. Their language was English infused with words from their former homes, which some people describe as a creole. It survives to this day.

The family unit among slaves had a much broader sense of community. A child might be raised by cousins or uncles who were not related to them by blood. It was a necessity of the time.

While slaves were not allowed to legally marry or have families, owners often permitted it. Some may have consented to such arrangements to keep their laborers relatively happy, but there were other benefits. Not only did the offspring of slaves become the property of slave owners, perpetuating the workforce, but a slave with a family was much less likely to run away.

It was hard enough to escape traveling alone; with a wife and children, it would have been nearly impossible.

Powers said all you have to do is drive through the ACE Basin south of Charleston and imagine the environment an escaped slave had to negotiate to find freedom -- miles of swamps, pluff mud and marsh grass filled with dangerous wildlife.

In some ways, the Lowcountry was a natural fortress.

Plantation life

By far, the greatest number of slaves worked on plantations.

South Carolina held such a concentration of slave labor because the Lowcountry's largest cash crop was rice, which required 10 times the labor needed to harvest, say, short staple cotton.

Bob Sherman, a historical interpreter with Middleton Place, notes that by 1860 there were 14 men who owned 500 or more slaves, and a majority of them lived in the Lowcountry.

Most of these slaves lived in cabins on the plantation grounds, small shacks that generally held 10 or more people. They made their clothes from cloth provided by their owners once a year, usually at Christmas. Also, they were given a pair of shoes meant to last an entire year but, Sherman said, most slaves would wear out footwear within a few months of work. By summer, most were working barefoot in the fields.

People imagine slaves toiling in fields between eight and 16 hours a day, but South Carolina plantations generally worked on a task system. For instance, one slave might be required to work a half-acre of rice in a day, and he had some leeway as to when he did it.

"I tell people on tour groups, 'These people weren't stupid, they wouldn't be out here in the heat of the day,' " Sherman said.

The division of labor on a plantation was simple. Field hands did the manual labor, and that included men, women and children. A female slave might be assigned to half as much work as a male slave, but she would be out in the field, even shortly after giving childbirth -- there was, of course, no maternity leave.

Even the children had to work. The Charleston Museum has in its collection a harness that slave children wore to tote tools, buckets or other supplies to field hands. It is sized perfectly to fit a 5-year-old.

Jake McLeod, born in 1854, would later describe his time on McLeod Plantation this way:

"The overseer's name was Dennis, and he was the one to look out for all the plantation work," McLeod recalled to WPA writers. "He lived on the McLeod plantation, and he was a good man to us. I had to thin cotton and drop peas and corn, and I was a half-hand two years during the war. If a whole hand hoes one acre, then a half-hand hoes half a acre. That's what a half-hand is."

During the war, McLeod was not yet a teenager.

These field hands were directed in their daily work by "drivers," who were generally older slaves. Although drivers were managed by overseers -- white men who were usually freelance employees of a plantation owner -- many overseers ran more than one plantation, and left daily management to the drivers.

Drivers had the worst of both worlds, Sherman said: one foot in both, welcome in neither. Drivers were forced to mete out punishment to slaves who did not perform, but they had no particularly special privileges.

The situation was ideal, and profitable, for the plantation owner. He left most of the decisions -- when to plant, when to harvest -- to his slaves, who knew the land best and had generations of experience. Rice planting had been practiced by Africans going back 1,000 years.

The former slave McLeod described life on his James Island plantation in its best and harshest terms. He talked about how his "missus and marster" would look after slaves when they were sick but also recalled how brutal they could be when a slave disobeyed.

"I run away one time. Somehow the overseer knew where I was," McLeod said. The mistress of the house "had me tied to the tester bed, and she whip me till the whip broke."

Disobedience was not tolerated on the plantation.

Off times

When they weren't working for their owners, many slaves worked for themselves.

A good number of enslaved people had their own gardens, and some even kept hogs or chickens. They sold these to make their own money, but they also kept some of their produce for themselves. A slave's ration of food provided by his owner was meager, so many of them supplemented their diet with food they had grown for their families. It was, in some cases, a necessity for survival.

According to legend, one slave who lived on a Cooper River plantation had come to the Lowcountry from either North Carolina or Virginia, and knew how to grow tobacco. She kept a garden of it, and turned a tidy profit selling her crops to locals.

The nature of the peculiar institution forced enslaved people to become quite proficient at a number of skills. Besides field work, a slave on a plantation might become a blacksmith or learn to make bricks. Fort Sumter is built out of bricks crafted by local slaves.

Sometimes these slaves would keep their skills in their extended family. A groomsman who cared for his master's fine horses would teach his son or nephew the work. Sherman said that drivers often taught their sons and nephews how to supervise other workers, when to plant, when to harvest.

Plantation slaves generally had their Sundays off, and Sherman said some would travel to neighboring plantations to visit friends or families. Some communities had patrollers to make sure slaves did not go where they weren't supposed to be. But clever people found a way around all these obstacles.

Amy Butler, a slave who worked in the countryside near Orangeburg, told an interviewer in Charleston in 1937 that slaves had to get tickets to go out at night.

When they snuck out to prayer meetings, however, they would "drag bush" behind them to erase their footprints.

"If the patrol catch you without (a) ticket, they beat you," Butler said.

Enslaved people had varying degrees of "freedom," although South Carolina was a more restrictive state than some.

This stemmed largely from the fear of slave uprisings, one of which was the rumored -- but never carried out -- slave revolt in Charleston planned by freedman Denmark Vesey.

These periods of unrest ran in cycles: New laws would be enacted to restrict the movement of slaves, to require slaves to wear numbered identification tags, and they would be enforced intermittently until they were finally ignored (owners didn't like to buy slave tags because it was a record by which to tax their property).

But life generally got even more difficult for enslaved people as the abolitionist movement, and talk of a Civil War, began to ferment.

City living

In Charleston, life for the enslaved was an entirely different experience.

Powers said that "domestics" made up only 6 percent of the slave population and, in some ways, were the aristocracy of slave labor. They had better clothes, ate better food (usually the leftovers from their owners' meals) and slept in fine houses.

But there was a trade-off. Besides the hard work of doing daily food shopping (there were no refrigerators), these domestic slaves kept the house clean, did all the cooking and hand-washed all the clothes.

Adeline Johnson, a slave who worked in the house of one plantation in the Upstate, told WPA interviewers that she worked exclusively in the house, waiting on the "missus" and the children. She recalled being whipped only once, for "marking the mantelpiece with a dead coal of fire." They made her "mammy" do the lashing but told her to quit after three licks. Johnson had learned her lesson, her owners decided.

Powers said domestic slaves had less privacy than those who worked on plantations. Sometimes they were even required to sleep in the same room with their master or mistress.

Elijah Green was a slave born in 1843 at a King Street residence. He belonged to George W. Jones, but when he was a teenager he was given to Jones' son, to act as a "daily give servant." In the 1930s, Green told WPA writers what his life was like in those days.

"I did all the house work till the War, when I was given to Mr. George W. Jones' son, William H. Jones, as his daily give servant, whose duty it was to clean his boots, shoes, sword and make his coffee," Green said. "He was First Lieutenant of the South Carolina Company Regiment. Being his servant, I wear all his cast-off clothes, which I was glad to have. My shoes was called brogans and had brass on the toe. When a slave had one of 'em you couldn't tell 'em he wasn't dressed to death!"

These slaves could be seen around Charleston every day, shopping for their owners or even working. It was technically illegal for a slave to hire himself out for work, although his master could rent him to another person. But most owners wanted no part of this bureaucracy, and slaves -- mostly artisans with specific skills -- could work with whoever would hire them. The slave's paycheck went directly to the owner.

Slaves who had a particular skill or a talent for a specialty, such as carpentry, were worth more than almost any other enslaved person. It was evident in the prices paid at that slave mart found by Charles Carleton Coffin after the war -- for Charleston -- had ended.

End of an era

On July 1, 1856, the city of Charleston outlawed the sale of slaves on the streets, where many auctions were held. Locals found the practice distracting, perhaps even distasteful, and had complained to city officials.

That same day, Ryan's Mart -- now site of the city's Old Slave Mart Museum -- opened on Chalmers Street.

Nichole Green, director of the museum, said that probably was no coincidence. The opening of the Mart centralized much of the city's slave trade, and Green describes a brutal system in the complex. Slaves were nothing more than commodities, cleaned up and well fed so they would fetch better prices. Slaves did all the cooking at the Mart, for themselves and the men who sold them.

The men who ran the Mart did not use physical punishment to keep slaves in line -- any person striped with the distinctive mark of the whip might scare off potential buyers: No one wanted to buy a discipline problem. So, Green said, the owners of the Mart would threaten to sell any misbehaving slave far away -- something no slave wanted. It would ensure that they never saw their families again.

The prices of slaves put them out of reach for all but the wealthiest citizens. In 1860, an "extra man" -- a slave with a particular skill, such as carpentry or blacksmith work -- might command between $1,500 and $1,600 (about $38,000 in 2011 dollars).

A field hand in the prime of his life and good health might bring $1,400 to $1,500. A "second woman," an older slave, might sell for as little as $800. Those prices dictated that 95 percent of all slaves were owned by 3 percent of the white population in antebellum America.

One telling detail: A light-skinned woman in this period sold for $1,800, far higher than any craftsman. In Old South cities such as Charleston or New Orleans, the practice of owners sexually abusing slaves was a not-all-that-secret practice. It is a little-known fact that some of the more than 3,000 freedmen living in Charleston were the offspring of slaves and their masters.

As one former slave later said, "If God has bestowed beauty upon a slave woman, it will prove her greatest curse."

Ryan's Mart shut down in 1863, when owners Thomas Ryan and Z.B. Oakes went off to fight in the war. In truth, business had fallen off quite a bit; by then Charleston was under siege by Union troops and most anyone with the means -- that is, anyone who could afford slaves -- had abandoned the city. It was the end of an era.

The slave mart had been closed nearly two years when Coffin broke into it in February 1865. He and another journalist took many of the papers they found and carried them back to Boston, where they now are archived in a library.

Those papers tell the story of an institution long since gone, but not forgotten.