⛰️ Cronk Sumark (Primrose Hill, 380ft)

Promontory hillfort guarding the Sulby Valley — the main natural corridor through central IoM. Though lower than the mountain peaks, this hilltop's STRATEGIC position makes it arguably MORE significant for detecting. It controls the river crossing and valley route. WHY: (1) Strategic hillforts attract conflict = weapons, military items, (2) Valley-guarding positions also controlled TRADE — tolls, markets, meeting places, (3) Cronk Sumark overlooks the Sulby River — the same valley the TT course uses because it's the natural route, (4) The area between the hillfort and the river (downslope) is where activity concentrated. Approach routes to the fort are also productive. This is one of the sites I identified in my terrain analysis as a priority.