Other day trips are usually within 20 miles or so of my house, or my sister's, and we'd likely be in her car, which she wouldn't abandon until the zombie hordes were in the mirror
The only trips I do fairly regularly that would cause me real trouble is the train up to Merseyside, about 270 miles each way. A map, even an A4 photocopy, would help, compass too. Wind up radio, purification tabs. But staying put until you know you've got no help coming would be important, this is real world and a complete breakdown is unlikely.
That said, I trust my gut. A train I was on stopped at Clapham Junction one time, and I smelt smoke. Nothing kept on happening, and I was more and more worried about it. Eventually I got out and found a seat on the same platform, but it wasn't for another 10 minutes that an announcement was made to evacuate the train. I'd been right in the middle of my carriage, and it was a packed train - if it had gone up in flames, I wouldn't have been certain of getting out.
One of the biggest problems I see is getting over large bodies of water: the Severn Bridge, the Forth Bridge, the Solent, for our IoW member, the Mersey, the Thames at Dartford. If the means of crossing is controlled by people you don't want to meet, or crossing is being refused, you need alternates. Not many people carry boats in their GHB!