Santiago       Santiago de Chile is a modern city with a booming economy nestled at the base of the Andes Mountains. A word of warning, Santiago's strong economy, industries and dense population comes at the cost of smog which often looms in the valley. But beyond the cities skyscrapers, outdoor lovers can venture an hour into the countryside for skiing, white-water rafting, and beaches.      As with any large South America city, Santiago offers an array of cultural activities, great restaurants and a thriving nightlife. The majority of Santiago's sights are found in the triangular-shaped historic core, Santiago Centro.      The Plaza de Armas is the city's historic centre and is surrounded by the main post office, town hall, national museum and the not to miss Catedral Metropolitana. On the northern edge of the Plaza you can explore the Mercado Central for crafts and Cerro Santa Lucia for its gardens.   Further north is Parque Metropolitano and the 863m the Cerro San Cristóbal, which is topped by the white omnipresent statue of the Virgin Mary. The summit can be reached by foot, bus or funicular and offers spectacular views of Santiago on a clear day.   Close to the Cerro San Cristóbal, on the edge of the Rio Mapocho, is Barrio Bellavista, a lively neighborhood with restaurants for even the most critical gastronome. If you stay up late enough, you can experience the nightlife and clubs of Bellavista. Another great area to party is Avenida Suecia, a commercialized pedestrian street full of bars and nightclubs