The Southeast is one of the best places in the US to spend Christmas due to its warmer climate and less likeliness of Snow. It's also home to some of the prettiest light shows, festive events, and holly jolly holiday fun anywhere in the US. While there are a lot of them I'm gonna touch on a few basics for picture limits and time.
Winterfest at Carowinds (Charlotte, NC/Fort Mill, SC)
This is actually a new event started last year, But the success of it combined with the other Cedar Point owned parks has made it an annual tradition that will possibly continue for years to come. Enjoy Ice Skating, lights, a 70 foot tall Christmas Tree, Rides (although the majority of the coasters are NOT open), Christmas shows, a Nativity petting zoo, lots of food options, and Snoopy and the Peanuts gang as well. Yes, there is even a Charlie Brown Christmas Tree.
Here is a video of the tree lighting ceremony.
Smoky Mountain Christmas (Smoky Mountains, Tenn.)
Sevierville, Pigeon Forge, and Gatlinburg, Tennessee are transformed into a Christmas wonderland every year with miles of lights, Christmas Shows, Attractions, and Dollywood's Smoky Mountain Christmas. Dollywood, unlike Carowinds, does run a big number of their rollercoasters during the Christmas Season. There is also craftsmen who make all kinds of things from Christmas candies, woodcarvings, blown glass, and lye soap. Dollywood also runs a nightly Christmas Parade through the park. Dolly Parton's two Dinner Theaters just off the park premises also host Holiday Dinner Shows. The area is also home to several outlet malls and theaters as well. There is also a Christmas Store and Hotel in the area which brings us to our next place!
The Inn at Christmas Place/ Christmas Place store (Pigeon Forge, Tenn.)
A hotel where it is literally Christmas 365 Days a year! All the rooms are decorated and the hallways and lobbies as well! They serve cookies and hock cocoa every day, Christmas movies are always available, and Santa visits every day. There are also indoor and outdoor pools, free breakfast, and other activities throughout the year there.
Speedway in Lights (Atlanta, GA, Bristol, TN, and Charlotte, NC)
This video is actually me driving through Charlotte Speedway last year at the Christmas display. These three NASCAR tracks offer a light show every year, but each track is different. So you're not gonna get the same lights at all three places. The drive is usually around 3 miles long at each track and takes an hour to complete depending on traffic. The traffic is very slow moving.
Biltmore Christmas (Asheville, NC)
The former Vanderbilt owned Biltmore Estate is adorned with Early 20th Century Christmas decor inside a Victorian Era mansion. There is also a winery, shops, and carriage rides on the Estate as well.
Christmas Town USA (McAdenville, NC)
A Christmas tradition in the town for many years has been the decorating of the entire town in Christmas lights. The event is called Christmas Town USA. The Christmas Town USA contains 375 lit trees and over 200 wreaths attached to city light poles. The lights attract visitors from all over the country and is one of the biggest light shows in the US. The show itself Begun in 1956 with the assistance of Pharr Yarns, the largest employer and landowner in the town, many trees and buildings in the town are covered in Christmas lights and some form of decoration. More than 300,000 vehicles visit each year. The lights are entirely maintained by volunteers from the community, and no admission is charged. Pharr Yarns pays the electric bill for the event. Located off Interstate 85 near Charlotte.
Oglebay Festival of Lights (Wheeling, West Virginia)
Kinda controversial depending on your stance as whether or not West Virginia is a Southern State or not (For all intents and purposes here it is). The Oglebay Festival of lights is considered to be a top-five light show in the nation.
Tanglewood Festival of Lights (Winston-Salem / Greensboro, NC)
Featuring over 100 displays and 1 million lights, this is one of the biggest light shows in the state of North Carolina (with only Charlotte being the biggest).
Disney World (Orlando, FL)
100 Miles of Lights (Virginia Beach to Richmond, VA)
An attraction that's pretty much what its name suggests. Several displays are lined up in the towns lined up on the 100-mile route from Richmond to Virginia Beach along the Hampton Roads region of Virginia.
I personally have been to Biltmore, Charlotte, and Bristol for Christmas lights. I must say they are pretty awesome that even the pictures don't do it justice. I have seen the lights in the Smokies as well but have never been to the big attractions at Christmas. Gatlinburg also has a big Christmas Parade every year that exceeds expectations. Kings Dominion which is also owned by Cedar Point also does a Winterfest evey year similar to Carowinds as well, so if you live closer there you may wanna check that out as well.