Documentation of the Palmyrene Tower-Tombs in Syria ... 
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2. ARCHAEOLOGICAL CONTEXT 
The oasis Palmyra, situated in the center ot the Syrian desert, was famous in antiquity because of its status as an important 
caravanserai. For a long time Palmyra was a politically independent city, but later incorporated into the Roman Empire. Because of 
the trade many cultural influences came to the oasis and were adapted by the Palmyrene people in art and architecture to express their 
self-confidence. For the inhabitants mentality the tombs are a very important source. The biggest group of Palmyrene tombs are the 
tower-tombs, of which 180 were preserved. 
A good documentation was required in addition to the ongoing archaeological research. Photographic documentation is able to show 
actual conditions but hides geometric information. Hence measurements were desired. It was impossible to realize scaffolding and 
manual surveying because of limitations in budget and time. Under these circumstances photogrammetry offers a cheaper and less 
time consuming alternative. Furthermore its application in remote areas is advantageous. 
The five best preserved tower-tombs were selected to be measured. For the very first time the geometry of each building was 
captured and is now precisely documented. Although facade maps produced by photogrammetry are usually less detailed than 
manually drawn ones, they are much quicker to produce and offer as well an important source of information. The following results 
were achieved: 
2.1 Referring to chronology 
Four of the five measured towers have dated building inscriptions. They were constructed between 9 B.C. and 103 A.D. in intervals 
of 30 to 50 years. The chronological evolution of building techniques is visible. The oldest tower was constructed using very small 
and irregular stones. In the course of time the used blocks of stone became bigger, more regular and formed an isodome stonework in 
the end. It is now possible to date towers that have no dated inscriptions based on this chronological differentiation. One of the most 
important results is the fact that from the 50s to the 80s of the first century A.D. a building boom took place. In that time a lot of 
western techniques and decoration systems were introduced in the tower architecture. References to hellenistic and roman styles, 
imported from regions like Asia Minor can be traced. 
2.2 Referring to dimensions 
The actual buildings reach a maximum height of 26 meters. There are no roofs at any of them. Thus the original height must have 
exceeded at least 30 meters. In relation to their footprint of 8 by 12 meters they can be classified as monumental. The monumental 
style required exact planning skills and experience. It can be assumed that within 100 years a well organized building industry and 
construction machinery with qualified workers was developed. 
2.3 Course of building 
With the facade maps the course of building becomes comprehensible. They reveal that size and form of the stones slightly change 
after some more or less homogeneous layers. This can be interpreted as different consignment of stones or maybe reflect the shifts of 
the workers. 
Pieces of decoration were integrated in a very unusual manner. Although the technology was supplemented with new solutions, for 
example the static equilibrium, the way to build was still very traditional. This is founded in the indigene form of the tower-tombs 
which depended on religious and cultic practices. In the middle of the second century A.D. the type of the tower-tomb was 
superseded by the more Roman-influenced temple-tombs and the old traditions were given up. 
The peculiarity of building techniques together with their changes during more than 100 years allow fundamental conclusions about 
the cultural conditions in Palmyra in Roman time. The extent to which old traditions were preserved or new technologies were 
adapted reflect the impact of foreign influences on the desert town Palmyra. 3 
3. PHOTOGRAMMETRY 
3.1 Standard photogrammetric processing chain 
It is not easy to define what “standard” means today because modem methods bridge the gap between analog and digital [Mikhail et 
al., 2001]. For this reason different methodologies were investigated. There is no doubt that the future is digital and many digital 
based methods already replaced analog ones. However, some analog techniques are still used (i.e. for image capturing) because a 
digital alternative is still too expensive or simply not available. Figure 1 shows the workflow for this project. Some steps of the 
workflow are redundant to compare analog and digital approaches. 
Before all thorough planning of every step was indispensable. It included especially the choice oi the camera and the block 
configuration because this affects the required method to solve the orientation problem. 
Three different cameras were used: 
- analog photogrammetric camera (Zeiss TMK 6), 
- analog réseau camera (Rollei 6006 metric) and 
- digital non-metric camera (Olympus Camedia 1400 L). 
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