We've seen scores of them during our few weeks in Australia. They descend on campsites and cafes, sitting around in groups chatting and drinking alcohol or coffee. They often wear the same kind of clothes and have similar hairstyles.
No, I'm not describing dreadlocked backpackers. I'm talking about the grey nomads, retired Australians who are out in force Down Under, perhaps replacing the backpacker as the quintessential traveller.
Since we left Beijing in July, my children Sam, eight, and Tilly, five, have not had many playmates - partly because kids in Australia have been at school and also because, as the dollar is strong, foreign tourist numbers are down. We have, however, met many grey nomads who are doing their bit to prop up the tourism industry.
On our first night camping, Sam got chatting to a grey-haired couple from Adelaide after he'd expressed interest in their head torch, which they then lent to him for the night. We couldn't help but notice their four-wheel-drive car with trailer (where a tent - very comfortable, they said - just flipped out on the top) and an assortment of other paraphernalia. Plus what looked like a fair amount of wine. Everything had come with them on the Ghan train, all the way north to Darwin, where it's warmer than down south.
Jennifer and Tom Gibbins, who retired from their teaching jobs in 2010, bought a caravan last August. The pair travel overseas for three months a year but are now on the road in Queensland towing their "comfortable home-away-from-home". They sometimes camp for free and sometimes stay on campsites to access power, water and laundry facilities.