Shipping from China to Riyadh, the capital city of Saudi Arabia, can be done through several modes of transportation, including air, sea, and land. The most common mode of transportation is through sea freight, as it is cost-effective and can handle large volumes of goods. It is important to note that shipping times can vary depending on the mode of transportation chosen, the distance between the ports, and the customs clearance process. Make sure to discuss these details with your freight forwarder to get an accurate estimate of the shipping time and cost.