Where Did I Go Wrong?

So anyway, it was our end of year staff leaving do/piss-up. I had a really good time but note the map below and my not so direct route home. I got lost, more lost, got to a roundabout which shouldn't have been there, and finally tried to retrace my steps, whereupon I ended up outside the police station, further back than from where I started, and finally i decided to bite the bullet and get a taxi back, by which time it was around 1:30am. I was very, very, drunk.