Security camera footage shows two goats briefly boarding a TriMet bus in Portland, Oregon, on Tuesday, 11 August.
The animals follow passengers through the middle doors, which close behind them, before reopening moments later. An overhead view shows the driver noticing the unexpected passengers and opening the doors again.
The goats then hop back onto the pavement as people help guide them away. They had been reported wandering loose in the area and later disappeared towards a nearby shopping centre.
The animals were eventually identified as Billy the Kid and Billy the Goat and reunited with their owner.