Taku is an abandoned city located on the shores of the northwestern Earth Kingdom. Prior to the Hundred Year War, the city was an important center of commerce. However, it was destroyed by the Fire Nation during the first wave of attacks due to its strategic location and importance to the Earth Kingdom.
Taku's primary purpose was to distribute cargo imported from ships throughout the entire nation. After the Fire Nation recognized its position, Taku became one of the first Earth Kingdom cities to be destroyed in the Hundred Year War. However, a small number of inhabitants remained in the area, and around 60 ASC, an herbalist began teaching at the city's medical institute. Eventually, her students left to help the Earth Kingdom Army, and the herbalist became Taku's lone resident. She continued to maintain the institute, providing medical assistance for the wounded Earth Kingdom soldiers that would occasionally traverse the area.
While journeying to the Northern Water Tribe, Team Avatar took shelter within an abandoned structure in Taku. Sokka had become sick, and Aang was prompted to search for ginger root so he could make a medicinal tea. He could not find the herb, but did come across a map that revealed to him the location of an herbalist institute. Fearing Katara would also become sick, Aang quickly set out to consult the herbalist; however, he was forced to travel without using his glider as a lightning storm had begun. Two watchmen spotted Aang from within a scout house as he was running across a mountain walkway, and a horn was sounded to alert Fire Nation authorities that the Avatar had been found.
One of the few remaining Earth Kingdom establishments in this area, the herbalist institute is hidden high in the mountains surrounded by natural growth. The institute is over 100 years old and was formerly a thriving establishment until the settlement was deserted. After the Fire Nation attacked, only the herbalist and her beloved pet cat, Miyuki, resided there, though wounded Earth Kingdom troops would occasionally visit the institute seeking medicinal cures. Its medicines were once sent all across the world. The location of the institute is important because the climate present is ideal for growing a variety of herbs needed to make medicines. A greenhouse is attached to the structure, holding what seems to be an endless supply of flora, some of which are considered to be the rarest in the world.