Taiwan has actively promoted the concept of "successful aging" in recent years. The Executive Yuan drafted the White Paper for Aged Society, which set the primary goal to enable seniors to deal with daily life more independently. Although ‘third places’ enable seniors to live independently, the third places that Taiwanese seniors like are not well understood. Consequently, by investigating third places, this study will investigate the environment of achieving successful aging and happiness among seniors. This study uses the questionnaire survey, and the data of this study were collected from October to November 2018 in Taichung City Central District. A questionnaire survey was conducted in several administrative agencies and participants were selected by random sampling among the over-55-year-old citizens who were already retired. An estimate of 90% confidence limits with 5% marginal error gave us a sample size of 257. This study finally received 200 efficient samples. The women’s top five choices of third places are the traditional market, supermarket, restaurant, daily necessities shop, and coffee shop. The men’s top five choices of third places are the traditional market, supermarket, daily necessities shop, restaurant, and a friend’s house. For seniors familiar with the concept of third places, the more often they go to third places, the higher happiness they achieve. This result investigates the importance of having awareness of third places for seniors. Therefore, we should encourage them to go to third places and engage in social activities frequently to achieve successful aging.