Double-decker bus
The first commercial horse-drawn double-decker omnibuses were introduced in England in 1847 by Adams & Co. of Fairfield, Bow, then improved upon by John Greenwood, who introduced a new double-decker in 1852.
Double-decker bus
Some of the existing double-deckers owned by SMRT Buses and SBS Transit were transferred to new operators Tower Transit and Go-Ahead under the Bus Contracting Model. Subsequent orders of B9TL and ND323F buses are being made by the Land Transport Authority, are painted in a lush green livery (rather than the operator-specific liveries of SMRT and SBST), and are used by all operators. Currently, there are more than 3,000 double-decker buses in Singapore, all of which are air-conditioned and the majority wheelchair-accessible.