Prague is an extraordinary combination of old and new, both architecturally and in terms of how things are done (and in many other ways I'm sure I have no grasp of.) 

The most beautiful red-tile-roofed buildings dating back hundreds of years are right next to modern office buildings; buildings with sublime steeples and carvings are right smack next to the ugliest souvenir shops and American exports such as [really] Hooters.

Similarly -- state-of-the-art sensors and sparkplugs are made at a run-down factory by workers handling chalk/ceramic dust without masks, but then quality-checked in a sealed monitoring system which can identify the date and time, worker, serial number, etc. of the component.  Should anything turn out to be amiss with the component, very specific corrective steps can be taken and recall information could be issued. 

We've had two outstanding guides: Vaclav Storek in Prague, who led us on our three-hour journey through the city, and Rikki in Vienna, whose historical knowledge was impressive but whose tour required more time than allowed for.  Vaclav in particular was able to pace things in a way that allowed us to absorb the information, and in subsequent days in the city, I found myself recognizing landmarks, recalling some of his remarks and explanations, and remembering his directions for how to take the Metro.

Kristina from ISP has been upbeat, patient, positive, and informative. Among the many other things I've appreciated, she has kept us all well-hydrated in this stunning heat by constantly distributing water bottles from a cooler compartment at the front of the bus. 

More momentarily. ~ Elisa