Hey! If you stay in Santiago, there's a lot places to go. First the historical center. You can start at the house of government called "La Moneda" and then walk to the other awesome buildings nearby. Another beautiful place its "San Cristobal hill". From the top of the hill you can take incredible photos of the city (of course if the smoggy air let you do it).
"Santa Lucia hill" it's another must go, Gabriela Mistral cultural center, and "Barrio Lastarria" also are very near. In the last one, there are very good restaurants and pubs.
There's a lot really, but if you have any other doubts just ask.
Enjoy your stay! over 2 years ago