1. Grim Fandango
2. The Longest Journey
3. Maniac Mansion: Day of the Tentacle
4. King's Quest V: Absence Makes the Heart Go Yonder
5. Monkey Island 2: LeChuck's Revenge
6. Sam and Max Hit the Road
7. Shadowgate
8. Police Quest II: The Vengeance
9. Myst
10. Leisure Suit Larry in the Land of the Lounge Lizards

Read the entire article.

Here's an alternative list by everyone, in alphabetical order.

Top 10 Adventure Games IGN Missed Out in Their Top 10 Adventure Games List

1. Beneath a Steel Sky
2. Blade Runner/Broken Sword
3. Dig, The
4. Full Throttle
5. Gabriel Knight series
6. Indiana Jones and the Fate of Atlantis
7. King's Quest III, VI and VII
8. Last Express, The
9. Neverhood
10. Riven