Walking in the UK and Europe may bring in the occasional rain shower and also when on a cycling holiday in Europe, you may encounter some wet weather. No longer does this lead to your maps and documentation getting soaked or disintegrated. There is a new generation of waterproof map cases and in this post John brings you tips & advice.

It’s not long ago that most people carried just a clear polythene bag to protect their maps and documents from bad weather. Many suffered the fate of their expensive maps dissolving into a blob of papier-mâché; rain water driven by the wind having infiltrated through the opening and small holes in the bag that had not even been noticed. There were some early 'proper map cases,' which claimed to be water resistant. They were essentially a pouch having a fabric back, clear plastic front and a Velcro closure. However, in the rain the water seeped through the hairy Velcro to turn the map once again to papier-mâché, an insidious rising damp. The map cases were normally really tight and if you had to quickly put the map in it, say on the onset of a rain shower, it was easy to tear the seams of the case. The next generation barely fared better: this had a double seal closure actually in the plastic rather like a sandwich bag and would often pop open. Soon the plastic cracked along the seam around the closure rendering in useless.

The last 25 years however, there has been a real breakthrough with plastic design with the manufacture of Thermoplastic polyurethane (TPU). This is a class of polyurethane plastics with many properties including elasticity, transparency, and resistance to oil, grease and scratches. The resulting map case is truly waterproof - if the closure is properly fixed, and highly durable. It is made from an uncrackable slightly stretchy plastic membrane with welded seams that take a lot of stress. You need to look no further than the Ortlieb range of waterproof map cases, cycling map cases and document wallets for your active holiday.

To seal, you need to make sure the documents are totally in the pouch; then squeeze the case to purge as much air as possible from it; then tightly roll the end and engage the male and female Velcro tabs. Make sure the corners are rolled properly. The bag should now be totally waterproof and you are ready for your walking or cycling holiday. 

These present-day waterproof map cases are very good as well for carrying things like tablets and important documentation that could otherwise get wet in your rucksack.

Tips for using waterproof map cases

Fold to fit

Firstly, fold your map as best you can to fit into the waterproof map case. It is usually best to buy a larger map case than the document and then fold the case around the map area. If using a large map like a UK Ordnance Survey, you may want to prise off the cardboard cover so that you can fold it better. Try to fold the map along existing fold-creases if possible. It helps to make visible all the area that you are travelling through on the day, sometimes you can fold the map in a way that you can use it on both sides. Obviously with scales such as 1:25,000 this is hard to do as you can easily walk off your map. For cycling it is generally better to use 1:50,000- 1:100,000 scale maps. The thing you have to try to avoid as much as possible is having to remove the map to refold it which is hard to do in windy conditions and of course you will have to try to avoid doing this in the rain. If you have access to a good photocopier, why not make A4 or A3 panel copies from the map of the route you are taking? They will be the correct size for fitting into the map case neatly and you can always carry the original map in your rucksack as a backup or if you want to see the 'bigger picture.'

Avoid the 'Flap-Case' scenario 

Managing your map case is very important. Many beginner walkers can be seen striding across the hills with their map cases flailing about them in the wind, hitting them in the face and threatening to strangle and entangle them. With an ‘Ortlieb’ type case this is quite easy to rectify; either roll or fold the case and map into a smaller area which thus becomes more wind resistant. You could use large elastic bands to keep the map compact. It is quicker and easier navigating working on a smaller area of map, using your finger or thumb to press on and trace the route as you go, so you can quickly resume navigation from feature to feature. At intervals unfold the case to check on-going progress or features to come. If you are cycling, you don't necessarily have to have a purpose built handlebar mount to put your map on, although using it may be easier. Some people like to keep their handlebars uncluttered as much as possible. You can wind a map case around the top tube of the bike frame, hold with bungees and just move it as necessary.

Negative issues of waterproof map cases

Very few! After 8 years of use, though the plastic was still in very good condition, the Velcro seals on my Ortlieb map case eventually separated from the plastic! but these can be refixed using an appropriate bonding glue. Obviously, you need to keep Velcro closures clean. The plastic also yellowed slightly. I bought a second A3-sized Ortlieb, now 4 years old, no issues as yet. I have also bought an A3 map case made by Silva. It is similar to the Ortlieb, but has sandwich bag type seal which is not as strong as a Velcro and roll seal. It can pop open if the air is not purged properly from the case and care is needed to make sure that the map does not overlap with the seal.

The other option: Waterproof maps

So, why not cut out the map case altogether and just use water proof maps? This option is fine, although there are comparatively few maps that are waterproof. Harveys Maps are mostly waterproof: they are a print-coating on a plastic sheet backing. The O.S went down the route of map lamination with their folded series. The drawbacks? After heavy rain the coatings on Harveys maps can wear or scratch off the map easier. The Laminated OS ‘Active’ maps are plastic coated weatherproof versions of paper maps, they are more durable and can still be folded. However, over time the plastic will crack and let in water, they also tend to be a little bit heavy.

Looking for more information or have any questions on waterproof map cases? You can contact John and the Walkers' Britain team via our website, email or phone.

Some waterproof map case producers:

• Ortlieb A whole variety of map cases and 'safes' are made for ipads and mobile phones etc.

• Silva the M30 from Silva is a durable and functional map case which protects your map whilst allowing you to navigate even in heavy rain. Its fully transparent design allows you to view your map from both sides of the case while the comfortable enclosed neck strap provides a secure and safe way of keeping your map on your person and ready for action.

• Aquapac see the Stormproof and Waterproof Kaituna Map Case

• Sea to Summit Large Map Case Made from TPU, totally welded construction and a super-strong Ziploc closure to provide fully waterproof and dust-proof performance. Designed with a detachable neck strap and corner anchor points for versatility.