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How to Map your Trek in Nepal

Posted by mapmeld on 17 May 2014 in English (English)

Langtang National Park map

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.

beautiful mountains

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.".
Location: Pasang Lhamu Highway, Godam, Bagmati Zone, Central Region, Nepal

How to Map an Atoll

Posted by mapmeld on 8 April 2013 in English (English)

My GPS trace

Me and my OSM Shirt

What did you map?

I collected a GPS trace between islands of Majuro Atoll, Marshall Islands. Majuro is a long string of islands at most a few city blocks wide, and sometimes smaller than a house. During low tide, you can walk across old, solidified reef from the main island out to Ejit, Kemman, and other tiny populated islands.

What are atolls?

Great question! Charles Darwin went on a ship called The Beagle hoping to sort this out. His measurements convinced the geologic community that atolls come from a coral reef around a volcanic island. After millions of years of inactivity the volcano sinks into the lagoon, leaving the ring of coral islands behind.

Today you can just look at this GIF:

animated atoll formation

How to Prepare

  • Look at OpenStreetMap. Figure out where you are and where you are going.
  • Talk to a local person about where you plan to map. Best case: they come with you!
  • My sneakers and flip-flops were not good 'reef shoes'. I met a guy who'd been living on small islands for years, and he wore a cross between crocs and Batman. I believe they are called fisherman's sandals. Get these before you go to the atoll.
  • If you're using your phone's GPS, try out an app such as My Tracks (Android) in airplane mode before you go the atoll.
  • Visit a site such as tide-forecast.com to see when the tide is lowest. To maximize your time, arrive before low tide. Find out when high tide is, so you can finish your trip before it comes. Don't trust the timetable: see if others are crossing.
  • Don't cross when tsunami waves or bad weather are expected. Even a small tsunami causes a fast current between islands.

What to Bring

  • Bottled water, crackers, first-aid kit, and sunscreen in backpack
  • Backup clothes (you will get wet)
  • Backup footwear (in case you lose a shoe)
  • Camera and GPS for mapping
  • Local phone (separate from GPS, so your battery doesn't run out)

My Experience

Where to Go

I went mapping on Majuro Atoll about three times. Each time I started from the Djarrit / Rita end of the main island and walked west, once as far as the island marked Bwokwmeej. The tide came in while I was walking, and I ended up catching a boat ride back to shore. A smarter traveler would probably stop at Amiel.

The Taiwanese ambassador said that you could walk from the Laura end of the main island and go north, to Ajokwala. My boss explained that this is possible only during low tide, at certain times of the year, and you can't cross back to the main island on the same day.

One day I went mapping on Arno Atoll, which is several miles to the east. I didn't know the area well, and there was no cell phone service, so I only mapped on land.

Water Depth

I am short. Your experience may vary.

Water is counter-intuitively most shallow on the ocean side of the atoll. You will see people walking in a U-shape away from one island, toward the ocean, and then to the next island. See my GPS trace at the start of the post for an example.

The principal at Ejit warned me that small sharks are a real danger once the tide comes in, possibly even in knee-deep water. I saw several small fish, brittle stars, and a couple of fish which were about the size of my hand.

Once the tide starts coming in, it is fast. When water is nearly waist-deep, the current can easily make you lose your footing. There is a ferry at Ejit, so you can end your walking trip there if the tide is getting too deep.

Shoes and Clothes

I wore a T-shirt, knee-length shorts, and flip-flops. In the photo you can see I wore my State of the Map US 2012 "Map The World" T-shirt. Recommend.

After my first trip, a friend picked me up in his car. I brought a towel to keep the seat dry.

My flip-flops never protected my feet properly. You want to avoid having coral scraping at the toes and sides of your foot. You want the back of the foot to have a tight fit. You can't have closed shoes because water and sand is flowing all of the time. Fishermen's shoes appear to be the right thing to do.

A flip-flop slipped off between Amiel and Kemman islands. Fortunately it floated and I caught up to it. On another trip it broke and nearly stranded me. Walking barefoot on coral-rock is painful. I wish I brought sneakers or a backup pair of sandals.

Meeting Strangers

In the Marshall Islands, people say yokwe to greet each other. It is pronounced a little closer to yawk-way. Visitors do not typically walk very far between islands. People will be surprised to see you.

I've read The Most Dangerous Game. I was cautious at first.

Children on Ejit were friendly and curious. They have met many Americans through the Dartmouth volunteer program.

Beyond Ejit, you will see only a few people. On Amiel I felt completely alone, and was a little disappointed to see a sandal print in the sand. Islanders live on the lagoon side there. Islands to the west are so remote, that there is often only one house.

Respect for Property and Culture

Land is scarce in the Marshall Islands, so land rights are important. You cannot just camp on an island. You cannot just buy an island. If you are interested in renting an island or having a beach day, ask the RRE hotel about Eneko.

There is a small shipwreck and graveyard on the lagoon side of the island labeled 'Pegerian'. I saw them many times while traveling by boat to Ejit, but I did not pry.

You are not National Geographic. Avoid photographing naked people.

Mapping your path

If you drop GPX, KML, GeoJSON, and CSV files in CrunchTime.heroku.com, you'll get an animated timeline-map. Here's mine.

The tiniest island

Location: Rita Back Road, Majuro, 96060, Marshall Islands
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