How can I back up my holiday photos without using a laptop?

Graham and his wife take thousands of photos while travelling but aren't always near wifi - is there a cloudless alternative?

We take thousands of photos on our caravan holidays, and I like to back them up every day or so. At present, I take a laptop and an external hard drive, so I have a copy on the laptop in the caravan plus a copy on the hard drive in my car.

Is there a way to make backups from SD cards to hard drives without carrying a laptop? I should add that many of the caravan sites we visit do not have wifi, so cloud backup is not practicable. Graham

Backing up photos used to be a problem for people taking exotic holidays. I thought it had gone away, thanks to advances in technology.