I did a similar "pilgrimage" when I was in London to see my daughter early last month.
But I did a bit of "previewing" beforehand, with "Google Streetview".
A couple of examples (parts of screen dumps from Streetview):
The George Tavern:
A bit more west, Sydney Street:
This way you can do a survey and decide if something is worth a trip or not. Or simply check, beforehand,
how things look, if you are new to a place.
Charles Wheatstone's home can be seen this way (19, Park Cresent, Paddington, near Regent's Park tube).
"Street View" is an extension of Goggle Maps, based on full panoramic photographs, taken approx. every 30 ft
in all major (and even many minor) streets in most major cities in many parts of the world.
Go to the Google Maps site, zoom to England, zoom in on London till you see Regnts Park tube station/
If you grab the little orange man on top of the zoom in/out lever and hold him in the map, all streets
which are photographed will turn blue. Now drop him in Park Cresent, like this:
Wham - you are there! Navigate by clicking the arrows (or use Up/Down keys). Pan by dragging the "world"
with the mouse or the Left/Right keys. Page Up/Page Down keys will pan vertically.
(The blue Wheatstone plaque is almost hidden behind the pillars you stand right in front).
Here's a task: have a peek at the Lachenal address in Northington Street. You can't go there, it's too small,
put you can look into the road from John Street.
I did go to the Horniman myself. Brilliant concertina exhibition. Item 57 (Wheatstone baritone) intriged me:
it had much wider horizontal spacing than all other instruments.
Some nutter, like me, must have ordered it as a custom job...