What are some well known monuments or natural wonders in a spanish speaking nation that I can use in a projec?

I have to do a project for spanish cl. I need to pick a monument, historical thing, natural wonder, etc. I need to talk about it in spanish and I need to also make a model of it (so it can't be really hard to make please). For example, if this project were for another language I could use the eiffel tower, leaning tower of Pisa, Colosseum, etc. Please and Thank you! I'll take any ideas!