Piero's Door To Nowhere

Piero's Door to Nowhere is a written note found in Dishonored.

Transcript
''The "door to nowhere" has proven to be a safety hazard, but for me this project is an endless source of inspiration. With the proper application of energies, I believe I can transform the door frame into a window of sorts, one that will allow a traveler to cover the distance from my workshop to some distant, arbitrary point in a single step. Currently the step leads to a sheer drop, straight down into the courtyard, but in time it will bridge gaps that will boggle the mind. Such work is many years away, to be sure, but if I survive the plague I'm sure to succeed.''

Location
The note can be found on the wall of the second floor of Piero Joplin's workshop, to the right of the sealed door.

Trivia

 * Piero's door to nowhere appears to be a reference to Portal, the smash hit game by Valve. When Corvo Attano ventures outside, he can view the door's exterior side - with the same symbol on it. It can safely be assumed this is an Easter egg.
 * Despite the references made in the note, the actual "door to nowhere" does not function at the Hound Pits Pub.
 * Similar "doors" can also be found in the Mystery Foe challenge of Dunwall City Trials. Aristocrats will exit the map through them if Corvo gets detected.
 * In Dishonored 2, there are no references to any such devices. As Piero is dead by this point, it appears he never succeeded.

Videos
Pieros Tür zum Nirgendwo Porte de l'inconnu de Piero La Porta per il Nulla di Piero Дверь-в-никуда (Изобретение Пьеро) 皮耶罗的传送门