Places to avoid
The University halls sites (Ffriddoedd on Ffriddoedd Road and St Mary's on Lon Y Pobty) have 24 hour security, so don't even bother trying to sleep or dumpster dive there.
Accommodation and Sleep
There are several parks in the city - none big enough to hide a tent in, but possibly a bivvy. There is also an unused beach which might be alright for a tent; head southwest down Holyhead Road, and take the last entrance into the University's 'Normal Site'. Turn left from the carpark, and head down a little path through some trees. This turns into a drainage run - so be careful, it's muddy on the path! The beach is at the bottom of the path.
Oliver has found that dumpster diving in Bangor is near impossible. There are many supermarkets, but only one - Farmfoods - has an accessible bin. Morrissons, Asda, and Marks and Spencers lock theirs away, and Oliver has not been able to find the location of the Aldi and Lidl bins. The only one he hasn't tried is Tesco. He was told by campus security that the small shop on the Ffriddoedd Road university halls site is also unsuitable, as there is a camera which is always turned on. You can get to Farmfoods by heading southwest out of the city on the main road towards Caernarfen. Farmfoods is next to McDonald's, and the bins are around the back. (Last checked: November 2016)