The tower of the winds
The first time we visited Athens the tower we closed, but it was open the second time. It is found in the more modern Agora – the Roman Market area of Athens. The tower is arguably the world’s first weather station, contains a sundial, water clock and wind vane. The tower was build sometime between about 200BC to 50 BC, so is at least 2000 years old, and is in remarkable condition (well it has just been restored).
It is called the Tower of the Winds because each face should a different wind. The Roman Agora in Athens is worth a visit if you an extra hour or two to spare.
Temple of Hephaistos
The Temple of Hephaistos is one of two original buildings in the Ancient Agora in Athens. The other is the Church of the Holy Apostles. Hephaestus was the god of metal working, craftsmanship, and fire; essentially the god of engineers, and I find it somewhat amusing that the building dedicating the engineer is the one that survived!
Actually the building was used far beyond its original purpose, including as a Greek Orthodox Church, which partly explains its well-preserved state.
Church of the Holy Apostles
This church, which is found in the ancient Agora in Athens, dates to the 10th century. It is one of only 2 buildings from the Agora to survive intact.
Some of the original wall paintings still survive, and almost nobody goes into it. So if you want a few cool and quiet minutes in the busy Athens it is the perfect spot to spend a few solitary minutes.