On the 25th anniversary of the night people took hammers to the Berlin Wall, something that marked our world for decades. It stood for the Cold War, which seemed like it might doom us all at times, but never seemed permanent, this poorly put together line of concrete covered in graffiti. Every escape made the night it came down seem closer.
As noted before, Russia doesn’t get many visits in Doctor Who, nor does eastern Europe in general.
For my part, I dropped an alien ship on a portion of the Berlin Wall (at the worst possible time, naturally) in a convention adventure. Having run it twice, I should note that the PCs have dodged the secret police, kicked off a riot, smuggled people (and aliens) across the border and generally shown little respect for the Wall. As is only right.