The city itself is only mentioned in Daniel's diaries in Amnesia: The Dark Descent, but a small fragment of the streets of London can be seen in the Streets level of Amnesia: A Machine for Pigs, in ruins due to the manpig invasion of the city.
In 1839, Daniel, a young archaeologist, returned to his residence in Mayfair, London after he suffered an uncanny incident during his expedition in Algeria. Carrying with him a mysterious Orb, Daniel seeks answers by traveling across the city, meeting several well-known experts who inadvertently suffered horrible deaths. These strange murders soon became public talk around London, while Daniel himself, believing he was responsible for the incidents, fled to the Prussian woods near the Baltic Sea to Brennenburg Castle.
In The Dark Descent timeline, London had not developed any electric tools nor vehicles and may have been using torches as light sources for the city. The city might have also utilized carriages for transportation. Though not much is shown or revealed about London in this timeline, Daniel mentioned the city has a museum where Sir William Smith worked at, a university where Professor Taylor teach, and a hospital where Doctor Tate worked at.
Amnesia: A Machine for Pigs
At the time of A Machine for Pigs story, London had been using lamps as its main light sources, while vehicles had replaced carriages as a mode of transportation. Industries had also become abundant throughout the city, with the Mandus Processing Company being the largest industry in London. The company apparently belongs to the Mandus family, being passed for generations up to its current owner, Oswald Mandus. Another notable landmark of London at the time is St.Dunstan's Church. As the events of the game unfold, London was struck with chaos as an army of manpigs ravaged through the city, kidnapping its citizens to be sacrificed to The Machine. Eventually, Oswald himself manages to stop the invasion at the cost of his life, as London silently entered the 20th century.