Agatha Christie: Poirot Filming Locations
Agatha Christie: Poirot was filmed in London in the United Kingdom.
The Albert Memorial (Kensington Gardens)
The Albert Memorial
Poirot, Miss Oliver and Supt. Wheeler walk around the memorial discussing the case. Later on Poirot and Colonel Hughes do the same in episode 10x02 “Cards on the Table”.
Source: IMDb