Lying just a few hours from Siam Reap, this is the busiest border crossing between Thailand and Cambodia.
Ochheuteal Beach is Sihanoukville's main beach. There are many bars and restaurants, and there are nightly parties during the peak season! 
Stung Treng is the last major town before the Laos border (with Si Phan Don – or "4000 Islands" – lying just 50 kilometres away). It's simply a place at which to make a brief stopover and has nothing of any real interest to offer, except perhaps that it serves as a way to get to Ratanakiri.