From the back cover:
Moving On Up
Assassins, burglars, and other urban hunters rarely barge in through the front door. Rise to the roofs and see cities from a completely new vantage with GameMastery Map Pack: Rooftops. No Game Master wants to spend time drawing every building's sloping summit and shifting shingles. Fortunately, with Paizo Publishing's latest GameMastery Map Pack, you don't have to! This line of gaming accessories provides simple and elegant tools for the bust Game Master. Inside, you'll find 18 captivating 5" x 8" map tiles that can be combined into a variety of rooftop encounters spanning such locations as:
Alleyway Gaps * Chimney Gargoyles * Dilapidated Roof
Noble Terrace * Treacherous Gables * Watchtower Parapet
You can also use the breaks between the rooftops to form a maze of alleys, expanding the urban sprawl from GameMastery Map Pack: Marketplace. Finally, with GameMastery Map Pack: Rooftops, you'll be ready next time the adventure takes your heroes above the city streets!