La Rioja is the capital of the province of the same name, set at the foot of the Sierra de Velasco in northwestern Argentina. It is a hot, dry city — summer temperatures regularly exceed 40°C — and serves as a base for exploring the dramatic desert landscapes of the region.
The main draws are outside the city. Talampaya National Park, a UNESCO World Heritage Site, has towering red sandstone cliffs and canyons with ancient petroglyphs. The nearby Ischigualasto Provincial Park (Valle de la Luna) is one of the most important palaeontological sites in South America, with a moonscape of eroded formations and dinosaur fossils dating back 230 million years. Both parks can be visited as day trips from La Rioja.
The city itself is quiet and pleasant, with a handsome central plaza, a cathedral, and the Museo Folklórico with a collection of regional crafts and religious art. Come in winter if you can — the heat in summer is punishing.