SEATTLE--(BUSINESS WIRE)--Walk Score® (www.walkscore.com), a Redfin company, today released its 2015 ranking of the most walkable U.S. cities with populations over 300,000. New York, the nation’s most walkable city, has increased its lead over No. 2 San Francisco. The two cities essentially tied for first place in 2011. Walk Score Ranking of Large U.S. Cities Rank   City   Walk Score 1   New York   87.6 2   San Francisco   83.9 3   Boston   79.5 4   Philadelphia   76.5 5   Miami   75.6 6   Chic