For long-distance trekking, a guide is compulsory, and also necessary if you’re intent on finding the megaliths. An organised one-day visit from Tentena with a guide and vehicle (for up to four people) costs about 2,200,000Rp, and prices go up from there. The guides from Tentena generally speak English.
If travelling independently, arrange a guide at Wuasa, Bomba, Badu or at the tourist office or national park office in Palu. Guides start at 250,000Rp for day trips, more for trekking; few speak much English.
The roads around Lore Lindu are being improved rapidly, and many of the old hiking routes are used by motorbikes. Traffic is light, but if you're set on a more pristine experience, definitely tap a guide and make your expectations clear.
One of the best places to get into the jungle, where it's free of motor noise but rich in wildlife, is the trail between Doda and Gimpu (a two-day walk); but note there aren’t any megaliths on this route once you leave Behoa Valley.
A popular route is to start in Tentena, then trek from Tuare in Bada Valley to Doda in Behoa Valley before catching onward transport to Palu. For a longer (three-day) trek, connect Tuare–Moa–Gimpu on the west flank of the park.
Bring mosquito repellent and sunblock lotion. You'll want warm clothes since it can get cold at night. Conversely, during the day it can get very hot, so you'll need to have plenty of water.