This study presents the recently identified site of Solhan Kalesi [Solhan Fortress] in the Solhan Plain and evaluates the sites that have been documented in surveys around the Solhan district in relation to the Urartian Kingdom. Ongoing surveys since 2019 in this under-investigated region have covered the Solhan Plain, the mountainous region to the north, and Murat River Valley. In addition to Solhan Fortress, other Iron Age fortresses at Azat and Hazarşah in the northern Solhan Plain, İşaret Fortress in the mountainous region southeast, and Deriktepe and Sükyan in southern Murat River Valley have also been identified.

The Solhan District of Bingöl Province lies on a relatively small (950 ha) plateau in the mountainous landscape of Eastern Anatolia. Located 800 m northeast of the Yenibaşak village junction off the Bingöl-Muş highway around 6 km west of Solhan district center, Solhan Kalesi is situated on an oval-shaped hill 75 m above the plain at the southern tip of a northeast-southwest mountain range. In addition to the architectural remains of fortifications and building foundations, many ceramic sherds, slag, and obsidian fragments have been found inside the fortress and outside on the slopes.

The foundations of the fortification walls visible on the hilltop can be traced along the natural contours of the hill. Walls are three meters wide, built with the dry-stacked technique, and even preserved up to three-courses in certain sections. Fortifications are reinforced by bastions at regular intervals. South of the area where the natural bedrock is exposed nearby the fortified peak, the foundations of a rectangular (23x33 m) building consisting of at least five rooms accessed through a long hallway have been documented. Inside the fortress are three adjacent structures abutting the southeastern section of the fortification wall. The northernmost room has a rectangular plan (8.20x3.60 m), the adjacent room has a square layout (4.50x4.50 m), and the eastern wall of the southernmost room (3.20x2.50 m) abuts the fortification wall.

Two oval structures consisting of a single course of stones are found inside the fortress in an area close to the southeastern fortifications. Each one measures 2.10x1.50 m and was built with roughly dressed stones. These irregularly built, 60-cm wide walls are reminiscent of cistern entrances.

Except for two examples, ceramics from the site are made of a reddish-brown fabric with fine sand inclusions, self-slipped, medium- or well-fired, and in general wheel-made. Rim sherds indicate the presence of bowls, plates, and jars with and without handles. Sherds have also been found that are decorated with linear incisions. For example, a jar sherd decorated with a 4-cm wide band bearing an incised fishbone pattern between two horizontal lines and a handle sherd decorated with incised vertical grooves were found inside the fortress. 

In addition to ceramic sherds, surface finds include obsidian fragments, terracotta spindle whorls, and iron slag. Various-sized spindle whorls and slag indicate the presence of workshops.

The floorplan of Solhan Kalesi does not resemble the royal cities and provincial centers of the Urartian Kingdom. The fortifications are built directly on roughly dressed bedrock without the use of rock-cut terraces, and they encircle an ovoid area abiding by the topography and reinforced by equidistant bastions. No architectural remains inside the fortress show the characteristic traits of buildings known from Urartian royal centers. In fact, a wide enough area that could accommodate such structures does not exist at the site, nor have indicators been found to suggest the presence of a lower town. Therefore, this article may explore the possibility that Solhan Fortress might have been an Urartian tribal center.

Urartian tribal centers had spread across a wider landscape beyond the territory dominated by the Urartian Kingdom. The characteristic traits of Urartian tribal centers involve works of rock-carving and masonry such as rock-cut tombs, roughly dressed cyclopic walls, and rock signs.

The geographical location of Solhan Fortress outside the political territory of the Urartian royal centers makes it a good candidate for having been a tribal center. However, the characteristic rock-carved features known from Urartian tribal centers are not present at the site, and the fortifications were built with roughly dressed medium- and small-sized stones rather than cyclopic stones. The most outstanding feature of the fortifications is the regularly placed bastions. Fortresses possessing bastions with a similar layout are known from the southern Lake Urmia Basin in Northwestern Iran. No glazed/painted ceramics from the Medieval Period have been found at Solhan Fortress. Incised ceramics from the site date to the Iron Age, A corroborated by the presence of iron slag. However, the architectural features noted above indicate that the fortress is distinct from Urartian settlements. The layout of the fortifications demonstrates that the site had been built as a pre-planned construction project and could not have been a temporary or seasonal settlement like the Urartian tribal centers. In the absence of clear chronological markers, the construction date of the fortress may date to any period between the Middle Iron Age and the Medieval Period. A more acute chronological assessment of Solhan Fortress will only be possible through on-site excavations and continued surveys in the region.