We're building out a local directory of denstists and there are lots of opinions on how to structure things for optimal google indexing. The idea is that someone searching for a dentist by city, zip or neighborhood should find the site organically.
Keeping in mind that there are approx 44k zip codes and 25k cities, many questions arise, and in truth the discussion makes for a great exercise in seo best practice in general.
Take San Francisco, CA as an example:
1. Would google prefer having one path of follow links that will list each dentist only once, and make all other browsing methods nofollow/noindex?
CA > San Francisco > Listings Page 1 > Listings Page 2. (This method would result in 25k main landing pages nationwide and MANY with secondary listing pages.
CA > 94112 > Listing Page 1 > Listing Page 2. This method would result in 44k main landing pages nationwide - but one level up - and SOME with secondary pages.
2. Would google allow 2 or 3 methods of follow links and index them all, considering that it would be over a hundred thousand links in total nationwide. (Each section would have some unique listings though listings would overlap in each section?)
Browse by city
Browse by zip
Browse by neighborhood
Smalltown, USA where many cities have 1 zip and no neighborhoods, resulting in the 3 sections having exact listings, it can have canonical links from one to the other)
If you lean towards 1, would google consider the other nofollows "link sculpting", even though it would be helpful to human visitors?
Pile on your thoughts....