There is a courtyard gallery in the Palazzo Spada in Rome that is designed to fool the eye. It looks like it should be 37 metres long, but in fact it’s only 8 metres in total.
The techique of forced perspective manipulates the way we see and process our sight in order to trick us. You may have seen one of those optical illusion rooms (called “Ames rooms”) that make people look taller or smaller depending on where they’re standing… or perhaps you remember the forced perspective tricks employed when filming the Lord of the Rings movies. Well, it turns out that this technique is a lot older than both.
The Roman Baroque architect Francesco Borromini enjoyed playing with geometry. When redesigning a section of the Palazzo Spada in Rome in the 1630s, he decided to experiment with forced perspective, and the result is impressive.
This is what it looks like: a courtyard gallery with a flat mosaic floor, surrounded by columns and capped by arches. It looks like it stretches thirty-seven metres in, with a life-sized statue at the far end.
This is what it actually is: a gallery just eight metres long; the statue is a measly 60 centimetres high. Everything was precisely calculated to appear larger and longer. The floor tilts upwards and the columns and ceiling get smaller and smaller as they get further away, creating a convincing illusion of depth and distance.