I backpack to UK in jan but Im not too sure about scotland as I didt went there before, only south wales and london, for london, go to the monument in the evening, the sunset is like WOW but before that go to the tower of london (go in the morning), it will give u a dollar off for the monument so is ard 19.50 pounds for TOL and 2 pounds for monument and I don see a need to go inside the london bridge but at night make sure u go there, 2 long exposure to noted, one on the bridge itself so u need a ultra wide and one beside the sea where couples dates and lots of japanese and korean girls ard, another long exposure there. Go to the St Paul cathedral, the interior is fancinating but no photography is allow so shoot discreetly, shoot the london eye in the evening but make sure u find a good spot, also to note is the buckingham palaces, go early and book a slot near the right gate(got 2, left and right) the changing of guards is amazing, especially the music they played .. South wales is definatly more fun to explored than scotland =)