I recently returned from a week trekking in Nepal’s Langtang National Park. I did my best to collect data on the whole trip for OpenStreetMap. Here’s how you can do it, too.

Do it for fun

On a week-long trek you will spend a lot of time hiking, talking with your friends, and looking at scenery. You should also probably bring some books and things for downtime and rainy days.

Mapping can be fun, too! Think of it as a scavenger hunt where the goal is to find everything.

Difficulty

Langtang is easier than other treks in the country, and much easier than any IMAX film you’ve seen where people were climbing ice walls. That said - seasons matter, weather matters, your personal health and fitness matters. Research. I biked daily and got altitude sickness medication from a travel clinic to prepare myself. I felt under-prepared and wish I’d done some high-altitude hiking beforehand.

There are only a couple of well-defined trails, so it’s difficult to get lost. Every hour or so there are guest houses where you can get food or stay overnight.

Travel with a group so someone will know if you fall or get sick. This could be the most important advice you ever read. Travel with a group.

Things to bring

A towel, a thin blanket or sleeping bag, sunscreen, a light raincoat, a sweatshirt, a winter jacket and gloves, binoculars, Nepali currency (especially bills less than 1000 Rs), long paperback book or Kindle. Water purification tablets or UV wand, hand sanitizer, toilet paper and other countermeasures.

Bring multiple passport-sized photos so you can enter the country and get a TIMS card

For mapping: smartphone with standard US or UK charger, plus a backup battery that can recharge your phone multiple times. On my Android phone, I use the My Tracks app.

What you can get on the trail

Every guesthouse has roughly the same items. If you see a unique item it’s in your best interest to order it; not because it’s a specialty, but because it’s something different.

Guest houses offer vegetarian meals including eggs, pancakes, naan, pasta, pizza, fried rice, mo:mo: dumplings, cake, tea, coffee, beer, soda, and Nepali specialties. Dal bhat is the best Nepali food because you get rice, vegetables, and soup with infinite refills for all three. Dal bhat is also slightly different at each place you go.

You can buy more toilet paper, bottled water, and a recharge from most places, but it’s always good to bring your own TP, water purification, and backup battery.

How to map

Review existing maps

About half of the area is covered by good-resolution satellite photos from Bing. The other half is a nondescript blur. A couple of in-person mappers had already uploaded decent GPS traces, points of interest, and village names to OpenStreetMap. On Google Maps, satellite coverage is more complete, but the trails and other details are not mapped.

In your pocket

Whether you’re the bus and on foot, recording and uploading a GPS trace makes it easier to figure out where the road is. Even in a satellite-covered area, your trace can help answer questions like: is the imagery aligned correctly? Were changes made to the road? Where does the road go in this tree-covered area?

Recording what you see

The My Tracks app has a pushpin button which allows you to insert a short note about your location. Some of my notes include “shrine”, “Dorje Bakery”, and “Pilgrim Guest House closer to river”. Use the space to record a name properly or remember a good location later.

The monasteries and also the towers called stupas are part of Tibetan Buddhism. There are several rock walls, also called stupa, where the road splits and you’re expected to go around on the left side. All should be tagged as amenity=place_of_worship with Buddhism as the religion. Some say a stupa should be tagged tower=stupa, but I don’t know if it’s true, and it looks like an electrical power pole on the map. Our guide also showed us a rock with a hole through it, covered in scarves and other offerings. He told us local folklore involving the Adam and Eve of yaks. This appeared to predate Buddhism or Hinduism, so I tagged it with a different religion.

There are a lot of guest houses. I don’t think anyone is going to map them all, so just get what you can. From a humanitarian perspective, it might be more helpful to map schools, health clinics, wells, and other places frequented by local people.

Not worth mapping

• Military installations and checkpoints. They don’t like being mapped. Their stations move from time to time.
• Streams. I added pushpins at a few crossings, but the stream is too small to see or care about it on the satellite picture. You shouldn’t follow a streambed in real life because your GPS is too inaccurate to know which side of the stream you’re on. Ravines are steep and will contain dangerous rocks. Don’t wander off the trail at all.

Things to remember

• In another post I wrote “you are not National Geographic”. Avoid taking photos of people while they’re naked and in other personal settings. We wandered into a Buddhist monastery and everyone was ok with us being there, but we were asked not to use flash photography.
• I’ll also add “you are not Jack Bauer”. If someone does not answer your question or says they don’t know, they don’t know and it does not help to ask again. People might not have a name for a local landmark or a mountain. It may be useless to ask “how do you spell {word}?” because Nepali words do not use English letters, and many people who you meet are illiterate in both languages.
• If you have questions or requests, speak up. Your conversation partner may not understand right away. Talk through the situation and you may hit on the right word, tone, or pantomime that conveys your point. I thought back to a video I saw in driver’s ed where the driver talked through every situation. Real life example: “what is it? It’s meat? Okay I want to try it. You’re saying it’s chewy? Yes it is. Oh wow! It is spicy. I like it.”.