The Incas were super cool and did many awesome things, but their greatest achievement was definitely their big cities. They built these cities up high in the mountains, which is pretty crazy if you ask me. The best city was Machu Picchu, which is a super famous place that people still visit today. It's really cool because the Incas made it out of huge rocks, and they fit together so perfectly that you can't even slip a pencil between them! How did they do that? It's like magic! Plus, they built water systems in the cities, so they had fountains and baths and stuff. So, the Incas were really good at building stuff and they built the best cities ever!
