Thanks for that info, Humphrey, That could save me a lot of faffing about with map sheets in poly bags.

Although I've no experience of using waterproof paper, the husband of a Challenger I met a couple of years ago sells it online at https://www.weatherwriter.co.uk/ Worth a look.

Yea Geoff but this Ze-com Waterproof paper you mentioned can only, alas, be used with a laser printer or a photocopier (what they be? #*checks '80's retro hardware*). Close but no cigar . . .

What luck.
I have a laser, so this may do OK.
Worth a punt...

WeatherWriter do a Water- Jet paper for ink jets too. It's good, I used it this year - don't know how it compares with your recommendation though.

I've got away with keeping print-outs in an Ortlieb case so far, but sometimes I do have to change maps in the p**ing rain, so this stuff is now on Santa's list. Ta for the recommendation!

So if you just use a normal (cheap) inkjet printer does the print not run if it gets very wet?

I just use ordinary paper and ink, kept in an ordinary Ortlieb mapcase and I've never had a problem. I try to make sure I have one day's walking per side of paper, printed to scale so I can turn or change the page at night in the dry confines of my tent. Usually...

I'm useless with printing off map sheets

What I do is simply cut up the OS Maps. 6/7 maps from Dash are not that expensive. No worries about the area to be printed off. After use they go in a bin.

I've recently downloaded Viewranger maps on to my smartphone. These are for back-up and use sparingly. Most of the TGOC area is covered for about £16.

Kirsten. The MemoryMap product substrate is a plastic and using any domestic inkjet printer the ink bonds to the material. I tested this initially by submerging a sheet in my bathwater (don't even ask!). This had no effect whatsoever. Sure if you try really hard you can- reluctantly - get the ink to smudge. But it puts up one h*ll of a fight!

The material won't degrade or go into a sulk and turn into a soggy mass.

My route this year - output from Anquet at 1:50,000 - takes up nine sheets of A4. I added an additional blank page, making five double-sided pages in total. So costed out at £3.39 for the whole set. Simples!

But each to his/her own. Frankly I can't do with hanging a map-case around my neck, flapping in the wind. I also carry a Samsung Galaxy loaded up with complete 1:50 and 1:25 OS coverage of the entire Challenge area - and old-school paper maps of iffy sections. The Samsung smartphones have the huge advantage of replaceable batteries - no need to worry about finding a power point to re-charge.

I have used the memory map paper for a number of years and found it brilliant, as Humphry says it is not troubled by water. In the bath Humphry? really? tell me you wern't in it at he same time.

Humph, did your lovely smartphone not take a picture of you and your maps all together in the bath???

Thank you for that tip, btw: I didn't know a smartphone existed that takes replaceable batteries.

Ian C, you are always a fount of techno-wisdom! Whether travelling or Challenging, I still carry the tiny LW radio you recommended a decade ago