The Ko Rattanakosin Island area is the oldest part of Bangkok. Located by the river, this is where most of Bangkok's main historical attractions are, for example Wat Phra Kaew and Wat Pho. These impressive sights aren't the only things to do in Ko Rattanakosin however, and many of the other sights are within easy walking distance. 'Ko' is the Thai word for 'island', but this is no longer really an accurate term for this area. It was so named due to Bangkok's extensive canals in the late 18th century which surrounded the area but nowadays most are filled in and you'd be hard pressed to realize what there used to be while walking or driving around it.