Looks cool and sleepy, doesn't it? And so people thought who farmed its slopes until in July 1968, without any warning, it erupted, killing 87 people, covering an area of some fifteen kilometres in ash and lava...rocks weighing several tons being launched into the air.
But as activity, less violent but very dramatic, continued, it was put to good account in Costa Rica's burgeoning tourist business.....where else could you see this, for example?
Hotels began to be built offering their clients views of nature's fireworks from the comfort of their own rooms...or sitting on the terrace, glass in hand, while the volcano rumbled and spat fire at close range.
As the tourist demand increased, other activities prospered too. Hot springs establishments....bird watching visits to the wetlands to the north...fishing and windsurfing on Lake Arenal...
And just as well, because Arenal began to nod off again....
First the flow moved round to the other side of the volcano - depriving the expensive tourist traps of their main attraction - and now seems to have ceased completely.
No fireworks...no rumbles.
I still see some pretty misleading publicity about Arenal...I have no idea if the guidebooks have caught up with the situation...but eventually the distributors will run out of postcards and flyers showing molten lava running down from the cone and the businesses dependent on its presence will die or adapt.
Death or adaption has been the choice of whole areas of Europe where traditional industrial production was a way of life.
Coal mines, steel mills...filthy dirty things that ruined the health of as many as they employed, if not more...but regarded as essential to produce the necessities that the nation required to be independent.
Governments decided that they did not need to safeguard these industries any more...any more than they needed to maintain control of transport and energy supply.
The mines and factories closed, private enterprise took over the transport and energy industries - but never without a hefty subsidy from the public purse.
The same public purse that funded governments' preference for maintaining able bodied people on benefits rather than making any effort to replace the old industries with new.
Inculcating the dependency culture they would pretend to deplore.
Governments abdicated their responsibilities both to people and to nation, putting everything up for grabs in the name of the market.
Where everything which affects our lives is bought and sold to enrich others.
Pelf its only pride.
Governments - or rather the financial - media - political nexus which has replaced the traditional model - have been farming the slopes of green and pleasant lands undisturbed since they renounced their traditional responsibilities....their peoples drugged by the bribes of easy credit into falling into hedonism.
But the lotus are running short on the shelves of Tesco.
Governments - or rather the political - media - finance nexus which has replaced the traditional model - are savvier than the farmers on the slopes of Arenal in the sixties. They know that those waked from a drugged sleep can be violent - thus all the 'security' measures justified by the fear of 'terrorism'.
How long before there is a social explosion from the other side of the slopes that sends pieces of their corrupt edifice flying to destruction?
And should it come, and when it comes, remember that you, middle class, law abiding, protesting peacefully at the loss of all you and your parents worked for, will be treated as though you were a lawless lout on the rampage. For such you will be in the eyes of those who make the law. The law of the market.