It is estimated that in north Wales 30 per cent of all jobs can be directly attributed to tourism, but the fact that visitors spend their money in a variety of ways has a beneficial effect (25) other things too. Many village shops would have to close if they were not supported by income from tourists, and the money spent on local souvenirs can (26) local industries from going out of business.

Unfortunately, tourism also has disadvantages. (27) , many of the roads in the Snowdonia area are extremely narrow and tourist cars cause traffic jams. Some farmers and local merchants complain that they make it difficult for them (28) their work as car parks full up during busy periods and many visitors cause obstructions by parking across gateways, etc. In addition, in the summer, thousands of people use the network of footpaths across Snowdon and its foothills. Often the grassy surface is (29) , leaving rough stone or mud. This makes the paths hard to see, and it can be dangerous to walk on.

In 1959, the government of Egypt was working on a plan to build a dam on the River Nile. It was called the Aswan Dam, and it was intended to generate electricity and allow the river water to be used for agriculture. There was one big problem with the plan, though. The dam would flood a nearby valley that contained ancient Egyptian treasures, including two enormous stone temples.

It can be difficult for governments to choose culture and history over economics. However, if countries always made decisions like this, the majority of the world's ancient sites would end up being destroyed. Luckily, UNESCO stepped in. They formed a committee that tried to convince Egypt to protect its ancient treasures. With support from many countries, they were finally successful. The huge temples were carefully removed from their original site and moved to a safe location so that the dam could be built.

After their success in saving the temples in Egypt, UNESCO went on to save more sites around the world. They protected lagoons in Venice, ruins in Pakistan, and temples in Indonesia. With industrialisation changing the world rapidly, there were many sites that needed to be saved. Eventually, UNESCO formed the World Heritage Organisation to protect important natural and historic sites wherever it was necessary.

By now, the World Heritage Organisation has protected hundreds of sites ranging from beautiful natural islands to buildings in large cities and ancient ruins. If you're able to visit any of the many protected sites, you'll agree it was worth it.