An ancient city with several millennia of history that has modernized over time. Language can be a major barrier and restricted internet access make for an interesting experience getting around the city.
Football is religiously followed in Argentina and the capital is home to one of South America's biggest rivalry, Boca Juniors vs River Plate. Therefore, a visit to the historic La Bonbonera was a must followed by a city walk.
Hop on a 1-hour bus from Mendoza to relax at these scenic thermal baths. Tucked into the side of a mountain, the water park has pools of varying temperatures as well as kid-friendly/kid-free areas.
Close enough for a day trip from Santiago, the city of Valparaiso has several colorful hilltops with great seaside views. The famous Viña del Mar which hosts the yearly music festival is also a short bus ride away.
Resting between the snow-topped Andes and the Chilean Coast Range, visiting a viewpoint is a must to appreciate the grand landscapes. The capital is also modern and has good public transport for getting around.