The Photographic Studio and Lab of Fortuné Joseph Petiot-Groffier (1788-1855)
This lab is the oldest existing we know of at present (thanks to the receipts, the chemicals can be dated back as far as 1840-41).

From photography pioneers such as Niépce, Daguerre, Talbot or Bayard, no entire lab has been preserved, but individual ancient large format cameras […]