Spring has arrived, the weather is warming up, and people who stayed indoors all winter are heading outdoors. Shed your winter coats, ditch the car, escape the hustle and bustle, and go for a spring ride on a bike.

Urban Foldable Bike　　This urban foldable bicycle named Rotation is an entry in an international bicycle design competition. It’s called Rotation because of its unique folding mechanism. Unlike common foldable bikes that fold horizontally, Rotation turns the pedals and chain housing downward, exposing a small gap in the middle of the rear wheel (the rear wheel actually consists of two wheels with a gap in between), then retracts the front wheel into that gap in the rear wheel. This structure makes it fold into a more compact form.
　Backpack Mountain Bike　　Normally worn as a backpack, it unfolds into a bicycle when needed—that’s the Bergmonch backpack mountain bike. In just two minutes, Bergmonch transforms from a 9-kilogram backpack into a mountain bike. Research data shows that 67% of hikers experience knee and ankle issues to varying degrees, mainly because their knees and ankles bear several times their body weight when descending. The Bergmonch “backpack mountain bike” features a lightweight, foldable design that can be easily folded into a comfortable backpack in two minutes. Hikers can carry it on their backs up the mountain and ride it down, significantly reducing the strain on their bodies during descent. Additionally, to ensure safety while descending, the Bergmonch has a slightly larger front wheel than the rear one, and riders are advised to adopt a standing or semi-crouching posture to slide downhill.
　Children’s Bicycle　　Many of us had a little bicycle during our childhood, but how about this one—isn’t it cooler? This children’s bicycle is called B’kid, and it’s primarily made of wood. As we all know, preschool-aged children grow rapidly, so this bicycle features an adjustable design. It can be equipped with an extra wheel to become a tricycle or have its pedals removed to turn into a two-wheeler that only requires balance with the feet, suitable for children of various ages. When the child grows older, the seat and handlebar heights can also be adjusted, making it suitable even for taller kids.
Cardboard Bicycle　　This is a bicycle made of cardboard, created by Israeli engineer Izhar Gafni. By folding the cardboard in a specific way, its strength is significantly enhanced. The resulting cardboard bicycle is sturdy and durable, highly waterproof, low-cost to produce, and easy to recycle. Izhar is an accomplished mechanical engineer with extensive prior experience in designing and building carbon fiber bicycles. Apart from the brakes and chain, every other part of this cardboard bicycle—including even the saddle—is made of cardboard. The bike’s exterior is coated with a waterproof resin and painted. This cardboard bicycle is waterproof, moisture-resistant, and even stronger than carbon fiber, capable of supporting a weight of 220 kilograms. The cost to make one such bicycle is only about 10 British pounds.

Amphibious Bike　　This unusually designed bicycle is tailored for the city of Helmond in the Netherlands—an amphibious bicycle. Since Helmond has many canals that are part of the city’s road system, this amphibious bike allows residents to cycle on land and also move through the canals. Designed by GBODesign, this bicycle looks much bulkier than a traditional one. While this might limit its range of use, it’s still a fascinating solution for amphibious travel.
All-Terrain Bicycle　　The biggest highlight of the Hanebrink is its 20×8-inch ultra-wide tires, which allow it to tackle any terrain. With 14 gears and a rear rack that can carry up to 100 pounds of cargo, it’s perfect for hauling loads with ease. The Hanebrink was designed by Dan Hanebrink, a former member of the U.S. national cycling team and six-time national mountain biking champion in the U.S. It is equipped with high-strength suspension and 8-inch-wide thick tires, enabling it to handle everything from regular flat roads and rugged terrains to snowy and icy surfaces effortlessly.