Killing Fields & S21 Shuttle Bus Tour, a must-see tour while in Phnom Penh, now available on an air-conditioned tour bus. Free hotel pick up and drop off (with city limits) or drop off at riverfront, English speaking bus attendant, recorded English commentary, and video documentary onboard. Don't want to inhale the dust and fume on a tuktuk for 2 hours!? This half day shuttle bus tour is your best choice.