The general lack of zoning restrictions in Bangkok has led to the existence of significant office supply in a wide range of locations in the city, and the market perception of the CBD has evolved over the past 20 years. The original CBD was located on the Silom and Surawongse Roads, home to the vibrant gold market and other trading businesses. The development of modern office buildings in the nineties with larger floor plates could not be accommodated in this area and the CBD began to take shape in the eastern section of Sathorn Road