This cross-shaped window in the 13th century Church of Bet Meskel is puzzling for several reasons.

First, this is not one cross-shaped window. It is two cross-shaped forms that share an arm.

The cross on the left penetrates the wall. The cross on the right does not.

Which came first? Because the cross on the left goes all the way through the wall, it's tempting to say the cross on the right was a false start that was abandoned.

If so, why? If the cross on the right had gone all the way through, would it have disrupted the design scheme on the interior side of the wall, perhaps by being asymmetrical?

For that matter, why wouldn't such windows have been carved from the inside to ensure their proper placement within the decorative and structural scheme of the church's interior?

Also, when were the linear grooved design elements created in relation to the two cross-shaped carvings?

At first glance, the linear design elements seem to meander randomly over the surface. However, it's possible that carving the incomplete window on the right marred what would otherwise have been a symmetrical design. If that's the case, it means the cross on the right was carved last, cutting through a very pleasing symmetrical linear design around the window on the left.

Now, how did that happen? Things like this occur today when the people executing the work either don't understand the overall plan or haven't communicated well with the designer. It was probably the same when this church was built over 800 years ago.

If you want to see how I think the window might have looked if the design had been carried out as intended, please take a look at the PhotoShopped image below.

Another mystery is why the linear design in the lower left quadrant of the image lacks the grooves seen elsewhere in this feature.

Ordinarily, that would indicate that part of the church's facade had been restored. I understand best practices today require doing something to differentiate restorations from the original object.

However, if you look at my photo of the entire facade,* you will find the material in the lower left quadrant of this image is only a small part of a larger feature that extends to the right all the way to the end of the facade and beyond, growing wider all the while. To my untrained eye, it looks like an intrusion of a different type of rock into the rock that makes up the rest of the facade.

There are two possibilities. One is that at some point in the past, a very large piece of the facade developed a crack or a series of cracks more or less where we see the edges of the lighter-colored material. The rock inside the boundaries of the crack either fell out on its own accord, or was removed proactively as part of a conservation effort. The area where the original rock was removed was filled with the lighter material we see today.

The other possibility is the lighter material has a geologic origin.

I don't know which option is the more probable. What makes me lean in favor of the restoration option is that the linear design elements within the lighter-colored area in the lower left quadrant of the photo do not have the grooves we see elsewhere. That is something a restorer would do to distinguish the restored section from the original surface.

I'm sure someone - possibly a UNESCO staffer or contractor - knows the answer.

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