Bangkok is known for its luxurious spas, and a rainy afternoon is the perfect time to indulge in some pampering. The Banyan Tree Spa is one of the most popular spas in Bangkok, with a range of treatments that use traditional Thai techniques. The Mandarin Oriental Spa is another great option, with a range of treatments that use natural ingredients and traditional Thai techniques. For a more affordable option, head to one of the many massage parlors around the city, which offer traditional Thai massages at a fraction of the cost of a spa.