A few come to mind: Walking 40 min. (fast pace) every night back to our hotel from city center in Rome w/ stroller after subway closed for evening.
Eurolines bus from Brussels to Budapest -- 18 hrs. each way. Stuck in last row squeezed in between two people.
Traveled from Louisiana to Baltimore w/ family of 4 to buy a new car ($ 2000 cheaper there). Then took city bus for 50 cents each w/ baby and toddler, 2 strollers, 2 big suitcases, 2 carry-ons; and carseat. Then walked rest of way w/ above stuff to the hotel.