Towers seen from a distance...

...are everywhere in Europe. These are in Prague, as seen from the Charles Bridge.



Towers are particularly attractive when seen from the water. This one is in the Wachau Valley, between Linz and Vienna.



Here's the Golubac Castle, in Romania, once a watchtower perched high over the Iron Gates section of the Danube. A huge dam project begun in the 1970's eventually raised the river about 100 feet, and turned what had been the fastest, most dangerous part of the Danube into navigable waters.

A little farther along this stretch of the river we saw Trajan's Tablet - a marble tablet placed by the Roman emperor Trajan, to commemorate a bridge he built over the Danube. Before the Djerdap Locks were closed, engineers moved the monument high up the cliffs, above the new water level.