The Fibonacci sequence is a series of numbers where a number is found by adding up the two numbers before it. Starting with 0 and 1, the sequence goes 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, and so forth.
There’s a popular block “sculpture” in Green River that can be seen from the freeway that is based on the sequence.
Apparently it cost $145,292 to build it, there are several other art projects in the area.
Other examples of land art can be seen here.