Put oven rack in lower third of oven and preheat oven to 450°F.
Rinse turkey inside and out and pat dry. Sprinkle seasoning evenly in turkey cavities and all over skin. Fold neck skin under body, then tuck wing tips under breast and tie drumsticks together with kitchen string.
Put turkey on rack in a large flameproof roasting pan. Roast, rotating pan 180 degrees halfway through roasting, until thermometer inserted into fleshy part of each thigh (close to but not touching bone) registers 170°F, 1 3/4 to 2 1/2 hours.
Carefully tilt turkey so juices from inside large cavity run into roasting pan. Transfer turkey to a platter (do not clean roasting pan) and let stand 30 minutes (temperature of thigh meat will rise to 180°F). Cut off and discard string from turkey.