Nutty Narrows bridge is actually the narrowest bridge in the world. It was conceived by a man named Amos Peters, who decided to do something about the constant stream of squirrels meeting an unfortunate fate as they made their way across the road. The bridge can also be found in various US heritage registers and lists.
17. Animal Bridge, Montana, USA
This bridge stands over the Interstate 93 near Evaro, Montana. It's located on an Indian reservation, an area inhabited by Native Americans for more than 14,000 years.
18. Cattle Underpass, Victoria, Australia
Farmers in the Australian state of Victoria can actually apply to the local government for grants to fund the construction of these underpasses. The initiative was undertaken to avert dangerous situations involving big herds of cows having to be herded over busy roads.
19. Bee Highway, Oslo, Norway
This "highway" is the first of its kind in the world. It was designed to allow for bees to pass through the Norwegian capital safely. Bees are important to the global food chain, and Norway has decided to take action - a third of the 200 wild bee species found in the country are considered endangered.
20. Amphibian Crossing, California
Numerous animal crossings of this kind can be found in California. Drainage culverts are known to be used by various amphibious species, such as salamanders, and these crossings allow them to gain access safely.