When I was in Wales, they would periodically place various gates on the bike route. (Usually at the border of people's property or at the edge of a sheep pasture.) These would require you to get of your bike, walk a little twisty corridor, open a gate and get back on.
One variation on that we saw (on in Cardiff itself) also had a very narrow section that with two grooves in it. This required that you not only get off your bike and that you hold it at about a 45 degree angle. The grooves would provide a place for your pedals and handle bars to pass through. Next to this narrow spot was a wider spot with a 2 foot step for your body to go through. (I don't know that I'm painting a good picture of this.)
As we were trying to figure them out, this young guy comes whizzing through, and slings himself off the bike and then running along side it, pushes it through the narrow section and then gets back on his bike. All without missing a beat and in about three walking steps.
It was like watching a trick horse-rider on crack. My sister and I stood there with our mouths agape for a few minutes and then headed on or way.
That was the first (of many times) that I realized that there are people out there whose skill as a cyclist is just awe-inspiring.
