"Let's Relax Spa: Thonglor Spend your time in relaxation with spa and onsen services in the heart of Thonglor. Experience an elevated retreat, allowing time to flow slowly while providing tranquility that offers authentic serenity to the body with the finest of two Asian traditions. Discover Bangkok's onsen here at Let's Relax Onsen & Spa, a comprehensive spa experience over 1,800 square meters in the center of Bangkok, where you can immerse yourself in the spirit of calmness. Enjoy the onsen in the Sukhumvit-Thonglor area along with top-tier spa packages that come with traditional Thai herbal massages using fresh, authentic herbs."