Carningli is the craggy hill that hangs over Newport, on the northern edge of the Preseli Hills. Its hard dolerite is the cooled core of a volcano that last erupted about 450 million years ago, and at sunset it still looks the part. The top is ringed by the walls of an Iron Age hillfort, and the remains of Bronze Age hut groups are scattered between Carningli and Carn Edward. The common around it is open grazing for sheep, cattle and ponies, and is protected as a Site of Special Scientific Interest for its heathland.
The national park's circular walk from the town is 3.5 miles and takes about two hours, with steep, rough ground near the top. The reward is a superb view over Newport Bay and along the coast.