Folding bikes used to be crude, heavy, hard to ride, slow to fold, and once in a while they collapsed in a heap. But in the early '90s that all changed as rail operators and airlines began to tighten restrictions on bike carriage. Fortunately, bikes that could be treated as hand luggage continued to travel free, and so the concept of a super-compact folding bike caught on. Today there are more than 50 folding bikes, and thanks to developments in small tyre technology and frame materials, the weight, ride quality and performance of the best is similar to that of their rigid cousins. Folding bikes offer five primary advantages over conventional machines:

• Free & unrestricted carriage on public transport
• Almost thief proof
• Space-saving at home and elsewhere
• Multi-modal travel (such as rail/folding bike) is usually cheaper than a car
• High resale value

Not all folders fit in a suitcase, or fold in seconds, but they can be made significantly smaller when you're not in the saddle. And they generally travel free and without booking restrictions on rail, bus, underground, ferry or air services. It's that freedom to travel anywhere with your bike that gives folders a magic quality. A folding bike can open up entirely new ways of travelling.