Kavala, Meteora, Thessaloniki

In 2012, I took two trips to Greece, first to Kavala in August, then to Kavala, Meteora and Thessaloniki in October.

Kavala sunset complete with the fishing boat.

Kavala sunset complete with the fishing boat.

Kavala is a picturesque port in Northern Greece, close enough to Istanbul to be a long weekend trip by car. It is strung along the coast with hills behind it. The old part around and above the harbor is filled with restaurants, which serve excellent, if a bit touristy seafood. I made the mistake of driving up there with my car, and almost ended up being permanently stuck in a really, really narrow street.

Meteora is kinda in the middle of Greece and it is justly famous for its rock formations and monasteries that are perched on them. There are six monasteries, and you can visit all of them. (I think. I visited three of them, and that was enough. Once you have seen three beautiful monasteries with drop-dead-gorgeous views, you have seen them all.)

Thessaloniki is another beautiful port city in Northern Greece, and it has special meaning for me as the birthplace of Ataturk. (I didn't visit the house he was born, however. Next time.) It is exactly the right size for a city, neither too large nor too small and reminded me of Izmir. There are an unreasonable number of street cafes and restaurants, and the entire population of the city seem to be eating or drinking at every hour of the day. My kind of city.

It has a good Archeological Museum, and the Museum of Byzantine Culture is also very impressive. The Citadel has a good view and several nice restaurants on the way up with great views.

Brussels and Bruges

I put up the photos from the Oct 2014 trip to Brussels and Bruges a few weeks back, and again neglected posting about it on the blog. (Click the image to go to the gallery.)

In Brussels I stayed at the Hotel Metropole, apparently a well known place. (At least it was mentioned on the city tour that I took. What better endorsement?) It was old, grand and quite interesting if you are into 'character'. Plus, just the bathroom of my room was the size of a standard hotel room.

Food (and beer) is surprisingly good, given that I didn't try any of the really fancy places. One word of warning though: lambic is an acquired taste, and apparently one that I haven't yet acquired. On the other hand, all of the trappist beers I have tried were excellent.

Chocolate shops are thick on the ground, and somehow all of them are crawling with tourists, but I didn't try any in Brussels. The only one I tried was the Chocolate Line in Bruges, recommended by a friend, and I endorse fully.

Bruges was a day-trip from Brussels, and it is ample time for sightseeing, though it is pleasant enough to spend a few relaxing days as well.

Cologne photos

In February, I spent a weekend in Cologne walking around and taking photos. I have posted the photos a few weeks back but forgot to blog about them. Click on the photo to go to the gallery.

Cologne Cathedral, Cologne

Cologne Cathedral, Cologne

Cologne is a 'typical' German city: visibly rich, predictably clean and efficient, boring in a good sense. I spent most of my time in the Altstadt, which is filled with original and restored old buildings including the famous Cologne cathedral. This time I didn't have the time to visit the museums, which are supposed to be quite interesting, apart from a small one dedicated to Kaethe Kollwitz.

Self-portrait, Käthe Kollwitz. From WikiArt.iorg

Self-portrait, Käthe Kollwitz. From WikiArt.iorg

As far as I am concerned, she is one of the greatest draughtsmen, ever, and the museum didn't disappoint. It was small, but that fits with the scale of the drawings and prints.

Rome

Rome, the Eternal City. It is beautiful, full of history and life. I had a 5 day trip to Rome in the Fall of 2013, but 5 days is barely enough to check-off the major tourist attractions: the Colesseum, Vatican, Pantheon, and so on. Rome is so full of things to see that I didn't make a list of things-to-do, except one: I wanted to see the Pantheon.

Pantheon Oculus

Pantheon Oculus

At the end, I visited it twice, and it was everything I expected to be: it feels wonderfully serene because of the single, large space, and the quality of light from the oculus. The receding geometrical shapes of the coffered dome give it a sense of vast scale, and its not hard to think of the celestial sphere when contemplating the concrete one. It feels monumental without making one feel insignificant (unlike, say, St. Peter's).

Pantheon is about 1,900 years old, and still an engineering marvel. The concrete dome is 43.4m in diameter, the same as the height of the oculus, the circular opening. Thus, you could fit a full sphere of the same diameter in the interior. It is still the largest unreinforced concrete dome in the world. Despite some cracking, it has stood up to the test of time. How?

The basic idea of a dome is simple. It is an arch rotated around a vertical axis. Thus, just like an arch, it transmits the force of gravity downwards and sideways to the foundation (or to the walls, as in Pantheon).

It is this sideways component that causes problems in structural engineering of roofs of any sort, first because it needs to be balanced, second because it can lead to tensile forces as opposed to the compressive forces of simple gravitational loading and typical building materials like stone and unreinforced concrete are a lot weaker in tension than in compression. In a dome, the lower part experiences 'hoop tension', that is tension stess along the horizontal 'rings'.

Roman engineers used several devices to ensure that their work would last. First, they made sure that the foundations of the building was sound despite weak, boggy soil. They simply threw more material at the problem when the original foundation ring cracked because of differential settlement. They built a second, larger foundation ring outside the original one.

Second, they built nice, thick walls to carry the lip of the dome. You can still see the brickwork with relieving arches on the outside.

They lightened the dome by making it thinner and by using lighter stones in the aggrage, and even inserting empty terracotta vessels towards the top. The coffer decorations reduce the volume of concrete without significaly weakening the dome structure. They also took out a lot of weight from the very top by using an oculus, which technically functions as a compression ring.

The weakest part of a dome is the lip, because its there the hoop tension is largest. Even though they didn't fully understand the cause, Romans were aware of the tendency of domes to crack along the lip and they made sure that there are a lot of reinforcement in that area. For comparison, despite Michealangelo's design to try and avoid this danger, the lip of the dome of St. Peter's had to be reinforced with iron chains in the 17th century after cracks formed.

I hope to revisit Rome some day, but for now, I have the photos from this visit in this gallery.