avenue de la Motte Picquet
First, solve all the Paint-by-Numbers puzzles. (A couple of them don't quite have unique solutions, but as we'll see that shouldn't stop you from solving the puzzle.) Here are the solution grids:
The 13 images all represent mosaics of video game creatures and objects that are situated on the facades of buildings or bridges in Paris. They can all be found using the mouseover feature of the map at this site.
avenue de la Motte Picquet
rue de Seine
3, rue Auber
50, rue de Charonne
87, quai de Valmy
pont Saint Michel
20, rue du Faubourg Montmartre
rue du 29 juillet
rue Charlemagne
111, rue Oberkampf
rue Clavel
place d'Iena
1, rue Paul Baudry
Each of the ten street images in the puzzle was taken standing at one of these locations, and looking toward another one:
01 : rue Oberkampf, looking southish (8 → 6) 02 : rue du Faubourg Montmartre, looking south (10 → 2) 03 : rue Baudry, looking southwest (9 → 7) 04 : rue Clavel, looking southwest (4 → 8) 05 : pont Saint Michel, looking east (2 → 1) 06 : quay Valmy, looking southeast (11 → 8) 07 : rue du 29 Juillet, looking southsoutheast (13 → 5) 08 : rue de Seine, looking west (5 → 3) 09 : place Iena, looking east (7 → 13) 10 : rue Auber, looking west (12 → 9)
Following the path 12 → 9 → 7 → 13 → 5 → 3 on a map spells out an S. Following 10 → 2 → 1 spells an L, and following 11 → 8, 4 → 8 and 8 → 6 spells a Y. The answer is therefore SLY.