El Rastro is Madrid's iconic open-air flea market, held every Sunday in the historic La Latina neighborhood. Dating back to the 18th century, it stretches along Ribera de Curtidores and surrounding streets, offering a vibrant mix of antiques, vintage treasures, art, and curiosities. With over 3,500 stalls, it's a bustling hub where locals and visitors alike hunt for unique finds and soak up the lively atmosphere.