Architecture - Fibonacci Spiral Staircase - Vatican City

I photographed this awesome staircase in the Vatican, Rome.

Camera: Canon IXUS 100IS
Location: Vatican City, Rome, Italy

The staircase is base on the Fibonacci sequence, which I learned about years ago in university. It is an integer sequence also found in various plants in nature:

1, 1, 2, 5, 8, 13, 21, 34, 55, 89, 144, ...

The sequence Fn of Fibonacci numbers is defined by the recurrence relation:

F_{n} = F_{n-1} + F_{n-2}

with seed values

F_{1} = 1 and F_{2 }= 1.

The Fibonacci sequence is named after Italian mathematician Leonardo of Pisa, known as Fibonacci.

Here is the Fibonacci spiral: an approximation of the golden spiral created by drawing circular arcs connecting the opposite corners of squares in the Fibonacci tiling - this one uses squares of sizes 1, 1, 2, 3, 5, 8, 13 and 21.

Reference: https://en.wikipedia.org/wiki/Fibonacci_number

You can see the resemblance!