I was in the US Army in Mainz, Germany during the mid to late seventies.
My living accommodations were in the building you see there but to the left side of the quad on the forth floor.
So, my plan was to take a train from Mainz to Luxemburg and meet them there. The train trip required changing trains at least twice if not three times. I did not have a lot of cash (I was in the army). Since I had only a one-way ticket, I had to hold back enough money to buy another ticket if I missed making the connection with my grandparents.
During this time my grandparents were traveling to the Netherlands to visit relatives. They were flying into Luxemburg then driving to holland.
So, I arrived in Luxemburg the day before they were to arrive and got a room for the night. I determined that I would not be able to afford a second night and still have cash for the ticket back to Mainz. I also could not afford a cab to the airport. So, I walked from the train station to the airport using my belt to hang my bag off my shoulder for the hike. It was a long five miles.
My plan at this point was to spend the night in the airport. However, this did not work out as they closed the airport at 11:00 PM. I was able to put my bag in a locker for the night. I considered staying at a hotel and was walking to the hotel to see what it would cost. The walk was made interesting due to the pea soup fog I was walking in. It was so thick you could not see the other side of the road. I finally gave up the idea of the hotel and went back to the airport. I ended up sleeping on the edge of the curb under the overhang of the car rental return. I had to lie on my side to keep from falling onto the driveway.
My grandparents arrived that day and I rode with them to Holland. My grandmother purchased me a ticket from there back to West Germany. There was still East & West Germany when I was stationed there we were there to keep the Russians on their side of the wall.