Three adult skulls from Göbekli Tepe bear intentional deep sagittal carvings made with stone tools post-mortem. One skull has drilled perforation for suspension or decoration. Modifications performed perimortem on fresh elastic bone. Carvings unrelated to defleshing or scalping. Ochre applied to one skull found in ochre concentration. Skulls represent 15% of adult individuals identified at site. Human skull fragments dominate bone assemblage over postcrania. Cutmarks indicate decapitation on cervical vertebrae. Site lacks burials but shows ritual architecture with T-pillars. Carvings prevent cord slippage for display or ancestor veneration. No healing signs prove postmortem treatment. Modifications unprecedented in PPN Anatolia and Levant. Skulls possibly from secondary burial rites. Ethnographic parallels in cord-fixed decorated skulls. Göbekli Tepe functioned as hunter-gatherer ritual center.