Qal'eh means fort or castle in Persian, and a tappeh qal'eh is a mound with a fort on it, or in this case a fort that has turned into a mound. The one on the Soltaniyeh plain in Zanjan province is a low rise in the fields, with no standing walls, only a faint rampart and a scatter of brick and pottery. In landscapes like this, forts are a constant, because the plateau was crossed by armies, caravans and nomads in every age.
The best way to read the place is to stand on top and look around. You see a flat, open plain, a little over eighteen hundred metres above the sea, with the Soltaniyeh dome to the south-east, ridges in the distance, and the line of the road. From such a mound, a guard could see a column of dust for kilometres, and a signal fire could pass a message across the whole plateau in a few hours. The geography explains why this region was disputed between Iran's neighbours for centuries, from Parthians and Romans to Seljuks and Mongols.
The ground around is farmland, and a visitor should keep to the tracks and respect crops. In spring the plain is patched with green and gold, and larks and hoopoes are easy to see. Summer is dry and dusty, and the shimmer of heat makes the dome seem to float. Winter brings snow, which can close minor roads, so be careful when choosing your season. Early autumn, with clear skies and a touch of gold on the poplars, is a lovely time.
Zanjan, about thirty-six kilometres to the north-west, is the place for fuel, meals and a bed, and it is a large, lively city with students and a bazaar full of knives and copperware. On the way you will pass roadside stalls selling honey, walnuts and dried fruit. A packet of local biscuits and a flask of tea make a good picnic. Carry plenty of water, since the plain has very little shade, and cover your head against the sun.