Within the scope of the study, the Halil Dede Tomb in Aktepe Village of Ürgüp District of Nevşehir, which has not been included in the architecture and art history literature before, was analyzed in detail and described. The fact that the structure built in the Seljuk period was not recognized within the scope of architecture and art history and that it had not been subject to a scientific aspect before was seen as a deficiency in the field. In the study, the tomb of Halil Dede, one of the Khorasan saints of the Seljuk era, was tried to be explained in detail in terms of plan, material and ornamentation features; the origin and dating of the building, which has no information about it other than a repair inscription from the 19th century, it has been opened to scientific debate.

As is known, although it is not welcomed in Islam, the Turks did not give up on building monumental tombs after the deaths of people who were at important positions in the state or believed to have high spirituality, and they continued these practices throughout the ages. Grave monuments, which were started to be built as a reflection of the pre-Islamic beliefs of the Turks, were built traditionally for centuries in every period and region. Within the scope of architectural actions that develop in direct proportion to the raw materials offered by geography with the arrival of the Turks in Anatolia, the stone was included first in the material list, which also affected the design and ornament processes; on the one hand building plans have diversified, and on the other hand, monumental tombs have constructed depending on the rank of the deceased. Grave monuments, built with various plan types in every period and region, on a scale ranging from the simplest to the monumental, have become one of the building types that determine the architectural face of Anatolia.

Before explaining the technical and artistic features of Halil Dede Tomb, we need to briefly focus on the identity of Halil Dede; it is known that certain figures came to Anatolia in the 12th and 14th centuries to work for the spread of Islam in the region, in short, to carry out their duties as dervishes, and they were popularly called Khorasan Saints. It is believed that Halil Dede lived during the Anatolian Seljuk and Principalities period and that he was one of the seven brothers who came to Anatolia from Khorasan. There are different legends told among the public about Halil Dede. Even today, different legends glorifying the spiritual personality of Halil Dede are told among the public.

Halil Dede Tomb, which is the subject of the study, is in the Ürgüp district of Nevşehir. The tomb is located on a slope overlooking the valley in Aktepe. The building covers a rectangular area extending in the north-south direction. The tomb, built with the masonry construction technique, has a plan consisting of two parts. The building consists of an entrance with an iwan, which can also be called a preparation area, and an interior space with a sarcophagus in the middle. In the iwan section located in the north direction, the iwan opening faces the east direction. The iwan consists of three round arches, and two of the arches have a ribbed form, slightly protruding from the mass. The main space is reached through the rectangular opening under the middle arch of the iwan. The lintel stone at the top of the opening, which has flat jambs on the sides, hides the segmented arch form on the portal. The opening at the entrance from the iwan to the interior space is designed on a very small scale and emphasizes the spatial difference between the iwan and the interior space with the elevation of a row of stones at the ground level. The main space has a rectangular scheme, almost square. There is an earthen grave under the sarcophagus in the tomb, which does not have a crypt on the lower floor. There are inscription stones at the head and foot parts of the sarcophagus. “Mihail bin Halil” is written on the headstone of the sarcophagus. In the interior, there is a small window opened on the east and south walls. The upper cover of the tomb is a round-arched vault on the inside in the iwan section, and an oval vault close to the dome in the main space, while both sections are covered with a flat roof on the outside. The cover system in the main space is a unique practice. The eight-arched upper cover, formed by partially placing thinner arches between the thick arches that intersect each other from four directions at the top, covers a rectangular area close to a square with a dome-like vault cover. One of the main elements that support the vault to create such a dome-like effect is that the arches covering the main space, which is not perfect square, have a very wide round form, that is, close to an oval. In this way, the feeling of a flat but very wide opening covering a small area creates the feeling of a space covered by a dome. At the same time, the fact that the rows of arches, emphasized by a relief at the top, continue uninterruptedly from the ground to the level of two rows of stones supports this feeling.

In the tomb, which was built entirely with stone material, smoot-cut stone was used in the exterior corners of the façade, the entire southern facade and the interior, and rubble stone and rough-cut stone were used in other parts. The stone used in the construction of the building is a local material. The building material is described as soft and easy to process due to its volcanic character. Unlike the interior, which is in very good condition, the exterior of the building is in a very dilapidated state due to weather conditions. There is a lot of material loss and collapse, especially on the upper cover and on the façade walls along the western direction. The construction material shed from the building is piled up next to the building mass. It can be easily said that the Tomb of Halil Dede has a very unadorned exterior, generally devoid of any ornamental details. The only ornament that can be observed on the facade of the building is the inscription engraved on the stone inside the three-segmented arch on the entrance lintel. “Sahib-ül hayrat vel hasenat Hacı Mehmed 1254” is written on the entrance. This inscription, which is most likely to be a repair inscription indicating the repair of the building, indicates Rumi’s 1254 and therefore the Gregorian year 1838. It is noteworthy that there is more effective content regarding ornamentation practice in interior spaces. It has been possible to create a monumental impression in an area small enough to fit only the sarcophagus and for a single person to stand in front of the footstone. This monumentality is undoubtedly made possible by the eight-arched vault that descends almost uninterrupted along the body to the floor. Both the arch emphasis and the high-relief eight-segmented semicircular rosette placed at the intersection in the center have been increasing the lively appearance of the ceiling.

There are no strict rules regarding the construction of grave monuments, which are created by the combination of the aesthetic understanding of the region where they are built and the local materials. Also, the fact that they are structures only for visiting purposes has provided them with a free application area and allowed the grave monuments to show such diversity. As in all building types, some plan types in grave monuments were applied specifically to a certain period and region, some plan types were applied in a limited number and abandoned, and some plans even took their place in the architectural literature as unique examples. In light of all this, even if there is no clear information regarding the identity of Halil Dede and the dating of his tomb, it is thought that it is possible to evaluate the issue, open it to discussion and reach a conclusion based on tangible information.

At this point, it is thought that the first element that needs to be examined about the Halil Dede Tomb is related to dating. Rather than indicating the construction date of the building, the number 1838 is written on the inscription at the entrance to the main space; it is most likely that it is related to the repairs made by a charitable person during the 19th-century Ottoman period. The line “Sahib-ül hayrat vel hasenat”, which was written by mentioning the name of the benefactor Hacı Mehmed before the date specified in the inscription, is written on the buildings built to serve the common use of the people. This phrase, which means “the owner of goodness”, can be seen in the repair inscriptions placed after the restoration of damaged buildings, and it appears almost without exception, especially in fountains built for public use. The second element is related to the plan type and architectural details of the building. The scheme, which is composed of the iwan observed in the Halil Dede Tomb and an adjacent closed visiting area, brings to mind the tomb monuments of the Dehistan region, which include a preparation space, built by the Turks in pre-Anatolia. When the plan of the Halil Dede Tomb is examined, it is possible to say that the dual plan layout consisting of a tomb and iwan is one of the rare examples that are not repeated frequently within the scope of Turkish architecture developing in Anatolia. In the tomb, which refers to the Seljuk tradition with its cover as well as its plan, it is seen that the vault covering the main space is in a form that we can call unique, and unprecedented in the Ottoman architectural tradition. The eight-segmented vault covering, which covers the structure in the form of a continuous shell, has reminded us of pre-Anatolian Turkish tents as if referring to Seljuk architecture. 

As a result, when the plan, material and ornamentation details of the Halil Dede Tomb in Ürgüp Aktepe, which are discussed within the scope of the study, and the identity of Halil Dede are evaluated together; It has become clear that the tomb exhibits Seljuk characteristics in terms of structure and scheme, and that it was repaired in the 19th century after the destruction it suffered. As a result of the examinations, it can be seen that the repairs made in previous periods were based on materials and reinforcement. As a matter of fact, in the tomb, which has a very simple identity on the exterior, the main factors reflecting the Seljuk character are the plan, space setup and the covering system of the interior. Therefore, it is obvious that the Tomb of Halil Dede, a Seljuk period tomb monument, has preserved its Seljuk character despite the interventions it has seen over time.