Aside from being home to one of Thailand's most well known and beautiful temples (Wat Phra That Doi Suthep), the twin peaks of Doi Suthep-Pui offer some incredible adventure opportunities for those venturing to northern Thailand. There are small villages, minor temples and waterfalls to explore along the trail to the peak, as well as bungalows and a campground near the summit. If you're feeling particularly ambitious, a host of companies offer downhill mountain biking from nearby Chiang Mai with courses that run from amateur to expert.
Though the peaks are located within a national park, keep in mind that this is Thailand and amenities/upkeep here aren't exactly what they are in the west. For the experience, however, that shouldn't be an issue. Just make sure you have your information and resources set before you set off exploring one of the jewels of this beautiful and mountainous terrain.