Following the collapse of the Austro-Hungarian Empire, the Polish–Ukrainian War and the Polish–Soviet War, Truskawiec became part of Poland again. Administratively it was the seat of Gmina Truskawiec, located in the Drohobycz County of the Lwów Voivodeship. As the spa was not destroyed in these conflicts, activity resumed quickly, as early as 1920 and Truskawiec soon emerged as a popular spa destination. In the 1920s and 1930s, almost 300 hotels, villas and guest houses were built here. The town was awarded three gold medals as the country's best spa resort. Next to Krynica-Zdrój, it was the most visited and most popular resort in Poland. A number of notable Polish personalities visited Truskawiec during that era, including politicians (Stanisław Wojciechowski, Józef Piłsudski, Wincenty Witos, Ignacy Daszyński), artists (Eugeniusz Bodo, Adolf Dymsza, Julian Tuwim, Stanisław Ignacy Witkiewicz, Bruno Schulz, Zofia Nałkowska, Marian Hemar, Hanka Ordonówna, Jan Kiepura, Zofia Batycka, Antoni Słonimski), athletes (Stanisława Walasiewicz, Halina Konopacka, Janusz Kusociński) and Generals Stanisław Maczek and Kazimierz Sosnkowski. Numerous guests from abroad came there as well. In 1935, the Prime Minister and future president of Estonia Konstantin Päts visited the spa. Rajmund Jarosz, who was the owner of the spa since 1911, founded the Museum of Natural History ("Muzeum Przyrodnicze") and a salt-sulfur pool, later destroyed during World War II.