Out on the plateau of central Jordan, east of the Dead Sea and south of Madaba, the land opens into a wide, treeless plain of wheat and barley, with low stone walls and the odd shepherd's tent. On that plain stand the ruins of Umm ar-Rasas, and the castrum is its oldest part, a rectangle of massive walls that began as a Roman military camp. It is probably of the late third or the fourth century, one of many forts that guarded the empire's edge against the desert tribes, and a garrison of auxiliary soldiers lived here. Its Roman name has been forgotten, and in the Byzantine age the town was called Kastron Mefaa. The walls still stand to a fair height, and inside is a jumble of collapsed houses, cisterns and arches, with a few churches among them.
After the Roman army withdrew, the camp became the core of a town, with churches built inside and around it, and later Muslim rulers left their own traces. The settlement continued through the early Islamic period and faded in the ninth century. Wandering through you find doorways with carved lintels, vaults half buried in sand and courtyards where pomegranate trees once grew, and the quiet is almost total. Nothing is roped off, but the stones are loose and the ground uneven, so take care.
This is high, open ground, about seven hundred metres or more above the sea, and the weather is often windy. Summer days are hot and dry, with a hazy light, and winter brings cold winds and occasional rain that turns the plain green. In spring the fields are carpeted with wild flowers, poppies and anemones among them, and storks and larks pass over. The best time to come is in the morning or the late afternoon, when long shadows pick out the details of the walls.
The roads are the real pleasure. From Madaba or from the King's Highway you take narrow, quiet tarmac across the plateau, with long views, gentle gradients and almost no traffic besides the occasional pickup and flock of sheep. Surfaces are generally fair, with patches of gravel at the edges. Signs can be sparse, so a map or a phone with offline maps helps. Fuel is not available at the site, and the small villages nearby may have a pump of doubtful supply, so fill up in Madaba, about twenty-eight kilometres away, and carry water and snacks.