Gustav was a huge archaeology fan and Victoria would have been Nicholas's 2nd cousin once removed (good enough for a prime seat at his coronation 
. I wonder if it was either of those 2 factors that drew them together on the trip or if it was just happenstance that each party was in the area?
Empress Alexandra--Alexander II--Alexander III--Nicholas
Kaiser Wilhem I--Louise Baden--Victoria.
It was happenstance. Gustav and Victoria spent the whole of that winter in the Mena House Hotel on the outskirts of Cairo, for her health. Nicholas stayed in the Giza palace nearby, but met up with them quite a few times while he was there. Their Hotel was run by a British couple who also founded the Brookwood racing track (how's that for a piece of unrelated trivia!) and who ran it almost like a country house, only billing people if they felt like it. The hotel is still there,though: I stayed there as a child so this is why I was fascinated to find out more about it when I was researching Nicholas's tour. His own Giza palace has gone, but the gardens I think, are now part of Cairo Zoo.
I have to say: Nicholas was not greatly interested in archaeology! :-) I don't think George was either; they spent more time with their hookas and obsessing over the belly dancers.
