Saint-Sixtus Abbey of Westvleteren is a great place to have a splendid time with your buddies.
You can find it in Vleteren.
There are 6 hotels that are not far from Saint-Sixtus Abbey of Westvleteren, each of which offers convenience and comfort. The Hotel Recour and Hotel Callecanes ought to provide you with some, if not all, of the comforts you desire.
Your most convenient upmarket choice is the Romantik Hotel Manoir Ogygia, which is roughly 3 miles (5 kilometers) away.
After the day's wandering around has depleted your spirits, revitalize yourself with a coffee or two from In de vrede (Donkerstraat 13, Vleteren), a short 0.06 miles (0.10 kilometers) away.