The first thing to understand about Royal Mound 3 is that it is made of the island itself. Bahrain sits on a dome of limestone, laid down in ancient seas and cracked by millions of years of sun and salt, and the builders of the mounds quarried that very stone from nearby. The slabs are pale, flaky and layered, and where a mound has collapsed you can see them stacked like old books. Up close, you may also see small fossils in the rock, shells and tiny sea creatures that lived here when the whole area lay underwater.
That geology explains much of the island's character. Limestone holds water, and beneath the surface a layer of fresh water from aquifers fed by rain in the Arabian peninsula rose in springs on the island and at sea, one reason why people settled here at all. The same stone provided building material for walls and houses, for the fort at Qal'at al-Bahrain and for the royal tombs. The core of the mound is a chamber of fitted blocks, topped with layers of rubble and sand, a design that has withstood four thousand years of weather.
Riding in this part of Bahrain is simple, but notice the surface. Where the tarmac ends, the track is hard limestone with a layer of loose fines, quite slippery on a bike with road tyres, and the verges are patched with sand. Take the dirt slowly, and use the paved approach roads wherever possible. If you pause in the middle of the day, the heat reflected off the pale ground is intense, so stop in the shade of a wall and drink.
Madinat Isa is only a few minutes away, and a fuel stop there takes no time. Bahrain's roads are well maintained, and signs are in Arabic and English, so navigation is easy, even without a phone signal.
If you have time, find a quiet corner of the site and put a hand on the stone. It has been sitting in the sun for four thousand years, and still holds the warmth of the day long after sunset.