Trekking along tribal villages
Visit any or all of the three major markets Passar in Wamena. Walk to them or take the bicycle rickshaw. Roaming through the markets is fascinating and completely safe. These markets are not limited to fresh produce and fruits but are more like open air shopping malls - clothing, canned goods, electronics, car parts, farming implements, etc - truly an amazing selection of products. Please ask permission before taking photos since many of the patrons are from remote villages.
Regular shops, including rather well-stocked grocery stores, are typically located along the major streets. Shops selling locally produced art, implements, masks, costumes and touristy treasures are primarily on the major streets. Street vendors provide wonderful soups, a local version of sandwichs, and even excellent ice cream imported from England!
See the 400 year old mummy at Akima about 12 miles south of town, the village is about 200 yards off the main road. Take a minibus from Passar Jibama and have them wait, or just enjoy the walk back - stay on the main road and you can't get lost!
Just stroll around town, which is especially interesting near the outer "suburbs" where traditional grass huts are located amongst newer structures with metal roofs. Note that there are a couple of obviously military installations where visitors and cameras are not permitted. There are very few street signs so you should pay attention to landmarks, but you can always find a bicycle rickshaw to take you back to your hotel or to the nearest market if you do get turned around.
Local children seem to love having their photos taken - just pull out your camera and the viewfinder is instantly filled with smiling faces. Most will want to see the photo on your camera's screen just as soon as the shot is taken! Paying for photos is generally not required in town.
The bridge across the Baliem River near the main market is a great place to watch locals - washing clothes, swimming, fishing, digging out gravel - as well as seeing many Dani & Yali people from remote villages coming into town to buy or sell in the markets.
Be advised that most shops do not have outdoor lights and there are NO street lights - it gets VERY dark very fast after sunset, so time your excursions to be back at your hotel before sunset.