Charleston sells itself with pastel houses, palmetto trees and horse-drawn carriages, and the houses are as good as the postcards. What the postcards leave out is where the money came from. The city was founded in 1670 as Charles Town and became the richest in the colonies on rice grown by enslaved Africans. Its port processed around 40 percent of the enslaved Africans brought to North America before 1775, and in 1770 half of its 11,000 people were enslaved. The first battle of the Civil War was fought in its harbor in April 1861. Fires, an 1886 earthquake and Hurricane Hugo in 1989 all hit the city, and it was rebuilt each time.
Three days is the right length. The historic peninsula is about two miles long, the sights are small, and a good museum or an old church takes an hour, not a morning. Three days gives you one on foot, one on the harbor and King Street, and one outside the city at a plantation and a beach. More days mostly buy you more plantations and more island. Come for the history and the food and be ready to hear both told straight.
Day one covers the old town from Rainbow Row to the Old Slave Mart, day two goes to Fort Sumter, the International African American Museum and King Street, and day three drives out to McLeod Plantation, Folly Beach and Bowens Island. There's more on the country in the United States guide. Start on a Tuesday: St. Michael's Church is open Monday to Thursday only, the museum on day two and the plantation on day three are closed on Mondays, and the Old Slave Mart is closed on Sundays. Savannah is about two hours south, with its own guide: 3 Days in Savannah.