Updated: May 2, 2019
I first visited the Angkor Kingdom, in Siem Reap, Cambodia, in 2008 and was back a second time in 2011 as a "guide" to show my parents around.
On both visits, I opted for the 3-day pass to tour the ancient kingdom, the main cluster of historical sites near Siem Reap town. It was more value-for-money to go for 3 days (US$40 for 3 days vs US$20 for 1 day — before the fee hike in Feb 2017). It was also not possible to visit majority of the sites in the Angkor Kingdom, including Angkor Wat, in just one day.
To avoid confusions, I will use "Angkor Kingdom" to refer to all the ancient sites in Siem Reap and "Angkor Wat" is the famous temple complex in the kingdom. The Angkor pass is a ticket to the Angkor Kingdom, not just Angkor Wat.
My 3-day exploration routes in the Angkor Kingdom are shown in the map below.
Browse the Google Map.