Rapeseed flowers are in full bloom on both sides of an expressway in Baokang county of Central China's Hubei province, on March 4, 2021. (Photo: Xinhua)

The Baoshan-Lushui Expressway, highway and Nujiang River in Southwest China's Yunnan province are seen on March 5, 2021. The total length of the Baoshan-Lushui Expressway is 85.17 kilometers; it officially opened to traffic this year, and promotes the integrated development of western Yunnan province. (Photo: Xinhua)

Sections of a 1.72-kilometer suspension bridge for the Duyun-Anshun Expressway are joined in Guiding, Southwest China's Guizhou province, on Jan 18, 2021. This marks a key step for the 276-km expressway, the largest road project in the mountainous province. The expressway is expected to open in June. (Photo: Xinhua)

A section of a bridge for the Simao-Lancang Expressway in Southwest China's Yunnan province is seen on Jan 20, 2021. The expressway shortens travel time between the two ends of the expressway from 3.5 hours to 1.5 hours. Its operation is expected to boost joint economic development in Puer's downtown and in the triangle-shaped region consisting of Lancang, Menglian and Ximeng counties. In addition, the expressway will link the Kunming-Bangkok Expressway, the Lancang-Mekong "international golden waterway", and Lancang Jingmai Airport, which will promote opening-up of the border areas. (Photo: Xinhua)

Photo taken on Dec 30, 2020 shows a section of the Hainan Ring Expressway in South China's Hainan province. As the expressway from Baoting Li autonomous county to Haitangwan officially opened on Dec 31, every county in Hainan now has expressway access. Currently, expressways on the island total 1,255 kilometers, which is providing a high-speed tourism passage in the province. (Photo: Xinhua)

A bridge over the Shantou-Chaozhou Ring Expressway in South China's Guangdong province creates an intriguing scene, on Dec 28, 2020. The expressway is 82.23 kilometers long and connects Shantou, Chaozhou and Jieyang to further optimize the layout of the expressway network in eastern Guangdong province. It is set to lead the three cities to integrate development, and accelerate the area as it integrates with the Guangdong-Hong Kong-Macao Greater Bay Area. (Photo: Xinhua)

Cars cruise down a section of expressway from Ankang city to Langao county in Northwest China's Shaanxi province, on Dec 23, 2020. The expressway opened to traffic on Dec 23, which means that every county in Ankang city now has expressway access. (Photo: Xinhua)

Twisting and turning through lush greenery, a section of expressway from Sanjiang Dong autonomous county to Liuzhou city in South China's Guangxi Zhuang autonomous region stands out in an aerial photo, on April 15, 2020. The expressway provides a convenient channel for local agricultural products to be sent from remote mountains to cities. Guangxi has gradually formed a road network with expressways, national-level roads, provincial-level roads and rural roads, which provide strong support for local economic development and poverty alleviation. (Photo: Xinhua)

A section of expressway from Huaiji county to Yunan county in South China's Guangdong province cuts through the landscape on Dec 18, 2020. The 102-kilometer expressway is a cultural and ecological tour route of Zhaoqing city, which will drive regional economic development in northwestern Guangdong. (Photo: Xinhua)

A bridge for the Panzhihua-Dali Expressway pans majestically across the landscape in Southwest China's Sichuan province, on Dec 6, 2020 . At 41 kilometers long, the expressway connects Panzhihua in Sichuan province and Dali in neighboring Yunnan province. It opened to traffic last year, and is an important tourist corridor between Sichuan and Yunnan to promote the interconnection between the two provinces and facilitate economic development along the route. (Photo: Xinhua)

A dramatic aerial photo taken on Nov 12, 2020 shows an expressway (left) and a highway (right) hugging the side of a cliff in North China's Shanxi province. The expressway provides a convenient path to Hongni village, which is deep in the Taihang Mountains. As the expressway opened to traffic, the village started to develop tourism, photovoltaic power generation, and grain processing industries that have effectively broadened the channels for villagers to increase their incomes. By the end of 2018, all people in the village had been lifted out of poverty. (Photo: Xinhua)

Sections of the Jinan-Tai'an Expressway in East China's Shandong province stretch across the landscape, on Oct 27, 2020. The expressway opened to traffic last year and it shortens travel time between the two terminations to 30 minutes. It's also driving economic development along the route. (Photo: Xinhua)

The Nanchuan-Liangjiang New Area Expressway in Southwest China's municipality of Chongqing stretches across thickly forested mountains, on Oct 20, 2020. The 77 kilometers expressway connects Nanchuan, Fuling, Banan and Yubei in Chongqing. (Photo: Xinhua)

A bright spot of color characterizes the Qingshuijiang Bridge of the Jianhe-Rongjiang Expressway in Southwest China's Guizhou province, on Oct 11, 2020. With a height of 184 meters and length of 540 meters, the bridge is an important part of the high-speed project connecting the province's Jianhe and Rongjiang counties. Last year, the Jianhe-Rongjiang Expressway opened to traffic. It spans Sansui, Jianhe and Rongjiang counties in Guizhou province, with a total length of about 118 kilometers. (Photo: Xinhua)