Need some tips/suggestions re: northern England [View all]

Going to spend 4 days in Edinburg and probably 3 days in York. Been to Edinburg but it's been a long time. Is there anything offbeat to see there? Then we're traveling to York, one of our favorite cities in England. Thinking about doing some side trips. Maybe Whitby and the Yorkshire Dales National Park. Anything else worth visiting in the area? Also might visit Leicester to see the cathedral. We're big on Gothic cathedrals. Any other places worth visiting in the north?

Also, we're spending a week in London. Been there numerous times and have done literally all the tourist things. Any offbeat/weird or unusual things to do and see there?