The Crystal Palace Hotel (Shuijingong Fandian) is a funky work of architecture seemingly beached on the lake shore. It is certainly not walking distance from anything, but one of its selling points is its great restaurants, so maybe after cabbing it to the city, you can come back to the hotel and enjoy "exotic" European cuisine like French, Swiss and Italian, which are surely in short supply in the rest of Tianjin. Additionally, the Crysrock Bar serves up American food and hosts live music and dancing if you've had enough traditional Chinese culture for the day.