As its name suggests, the obelisk was erected to commemorate the visit of India's Governor-General, Marquis of Dalhousie. Designed by John Turnbull Thomson, you can clearly see the resemblance with London's Cleopatra's Needle. Note the four decorative lamps that are installed at the obelisk's corner.
Wikipedia https://en.wikipedia.org/wiki/Dalhousie_Obelisk
Address 1 Empress Pl, Singapore 179555
Coordinates 1°17'14.812" N 103°51'8.002" E