I listed Russia separately even though the more populous cities are located in Europe and the immense Siberian plain is in northern Asia.  I have always wanted to visit Moscow!  I think it would be a remarkable place to visit with its unique architecture.  Seeing Red Square, the Krelim, Lenin's Museum and the Bolshov Theater would be fantastic experiences.  Trips to visit Gorky park and Catherine's Palace would be great (no pun intended).  I would also like to spend some time in St. Petersburg and enjoy its culture and history.  I can imagine while most of the Siberian plains and Ural mountains are inhabitable these places would have to be some very beautiful and undisturbed areas.  Talk about if a tree fell would it make a sound?