The Palmengarten is Frankfurt's botanical garden — 22 hectares of formal beds, lakes, themed greenhouses and outdoor collections in the Westend district, just north of the city centre. The historic core, opened in 1871, is built around an enormous wrought-iron palm house (now the Galahaus) and a glass tropical pavilion that holds rainforest, monsoon forest, desert and mangrove sections. Outside, the landscaped grounds run through a rose garden, a heather garden, a Japanese garden and an alpine garden, with paths wide enough for the city's joggers and prams.
The Palmengarten doubles as a summer concert venue (look out for the Sommernachtsmusik series in July and August) and as a popular Sunday-walk destination for Frankfurt families. The neighbouring Botanischer Garten of Goethe University is free and shares a fence; entry to the Palmengarten itself is about 8 euros. Open daily 9am to 6pm, longer in summer.