If you're looking for a meeting place or a good stop around ½ or halfway between Trussville and Laplace, you can try Laurel, MS, which is about 3 hours southwest of Trussville, or about 2½ hours northeast of Laplace.
Other possible places to stop near the midpoint include Basic, Fellowship, Harmony, Nancy, Claiborne, Barnett, and Davisville.
About ¼ or a fourth of the way, you can stop at Knoxville, AL. This is a little over 1 hour southwest of Trussville.
About ⅓ or a third of the way, you can stop at Gainesville, AL. This is almost 2 hours southwest of Trussville.
About ⅔ or two thirds of the way, you can stop at Hattiesburg, MS. This is about 3½ hours southwest of Trussville, or about 2 hours northeast of Laplace.
About ¾ or three fourths of the way, you can stop at Picayune, MS. This is about 4½ hours southwest of Trussville, or a little over 1 hour northeast of Laplace.
If you drive straight through without stopping at all, the total distance is 383 miles. The distances shown above don't include local roads to get into each town, so if you're planning a long road trip, make sure you factor in traffic and road conditions, rest stop breaks, and interesting detours along the way. If you're in a rush, you can do the trip with zero stops, and your total travel time would be around 5 hours, 35 minutes.
