Unusual Barriers

"What the heck ARE those things?"  Sometimes I can almost see the thought balloons containing those words floating over the heads of tourists. In parts of Washington DC close to the Capitol or the White House, these bellows-like security features can be found at the entrances to underground garages,  making it impossible to drive in. They remind me of accordions gone awry or giant fireplace bellows being birthed from the concrete. They spend most of their lives unnoticed, compressed flush with the sidewalk so there is an element of surprise. The bright yellow color scheme gives them an unintentional air of whimsy. Lord knows we can all use a little whimsy in our security features.