Ascended 12,600ft to 12,700ft. From the Shira Plateau, we continued hiking to the east towards the Kibo Peak and the Lava Tower, called the “Shark’s Tooth.” We then hiked up to Arrow Glacier at an altitude of 15,997 ft, the highest point of the day before hiking back down to Barranco Camp (12,700ft). This day plays a big role in the acclimatization. I had stopped taking Diamox (altitude pills) before we started the hike. I tested them out for a day and immediately felt tingling in my feet and hands. It’s a fairly common side effect but was a bit concerning. The best acclimatization is water and going nice and slow. It was stressed by the guides that “Sea level fitness” only gets you so far until your body is used to working at higher elevations.