I've noticed a tendency for people living in other countries to be dismissive of the rate of how much cycling there is in the Netherlands on the grounds that "it's a flat country, so easy to cycle".
In fact, living in a flat country means living with headwinds. Strong headwinds.
I've cycled both in places with hills and in flat areas with strong headwinds. It's easier with hills. Hills don't go on for ever - after climbing a hill you get to ride back down the other side. If you're lucky enough to have rolling hills you can get part way up the next one with the speed you gain on the previous downhill. Excellent fun. On the other hand, once you start into a headwind you're generally stuck with it. Possibly for the rest of the day if you're touring.
The Dutch recognise this problem. You find a lot of upright omafietsen (granny bikes) are fitted with tri-bars. This applies even to omafietsen ridden by actual grannies (though the example in the photo is actually a rather upmarket machine ridden by a genuine grandad).
It initially looked to me like a bizarre combination, but it's quite practical. It's got nothing to do with pretending to be in a time trial and everything to do with a practical desire to minimise one's frontal area to go into headwinds with a little less effort.
One of the Dutch readers of my blog, Anneke, commented on a recent post that on her 16 km round trip to school each day she could "remember riding in a flock of school kids and arguing about who had to ride in front facing the strong winds."
To summarize, if flatness was all that mattered you'd expect that areas of the UK such as Lincolnshire, Cambridgeshire and Somerset would have a similar rate of journeys by cycle as the Netherlands. They don't. Not even the parts which are called 'Holland'. The problem is the lack of subjective safety. Riding on roads, sometimes with hostile motorists, does not make for a cycling experience which is pleasant enough for everyone to want to cycle. This is what is so different in the Netherlands and the reason for the high rate of cycling here.
What's more, Switzerland has a higher cycling rate than any English speaking country, and it's anything but flat. So, can we please stop making this excuse about hills ?
We organise cycling holidays in the Netherlands - when possible we take into account the wind direction.