People visit Caravan Salon in Dusseldorf, Germany, on Sept. 4, 2020. Caravan Salon, a trade fair for caravans and motorhomes, is held here from Sept. 4 to Sept. 13, attracting around 350 exhibitors. (Photo by Tang Ying/Xinhua)

People visit Caravan Salon in Dusseldorf, Germany, on Sept. 4, 2020. Caravan Salon, a trade fair for caravans and motorhomes, is held here from Sept. 4 to Sept. 13, attracting around 350 exhibitors. (Photo by Tang Ying/Xinhua)

People visit Caravan Salon in Dusseldorf, Germany, on Sept. 4, 2020. Caravan Salon, a trade fair for caravans and motorhomes, is held here from Sept. 4 to Sept. 13, attracting around 350 exhibitors. (Photo by Tang Ying/Xinhua)

People visit Caravan Salon in Dusseldorf, Germany, on Sept. 4, 2020. Caravan Salon, a trade fair for caravans and motorhomes, is held here from Sept. 4 to Sept. 13, attracting around 350 exhibitors. (Photo by Tang Ying/Xinhua)