The Phnom Penh-Sihanoukville Expressway is the first expressway in Cambodia, it was also a high-quality cooperation project under the Belt and Road Initiative framework. It starts from Phnom Penh, the capital and largest city of Cambodia, to Sihanoukville, the second largest and the biggest port city of the country. The 187-kilometer-long expressway was invested, constructed, and operated by China Road and Bridge Corporation, adopting strict factory standards as well as original Chinese designs.