Is it okay for a 70-year-old man to travel with four children?

No. The physical condition of the elderly may not be suitable for long-distance travel, because age-related diseases (such as high blood pressure, diabetes, and heart disease, etc.) may be aggravated during the journey, and their hearing, vision, and memory will also decline, making them unable to function as young people. People adapt to new environments, which can lead to physical discomfort, which will bring a lot of inconvenience and difficulty. At the same time, children will be full of novelty after going out, which will be difficult to control, which will further increase the physical pressure of the elderly.