'Back to nature' was the dictum in the 18th century, so Friedrich Wilhelm II had this little Havel island turned into an idyllic playground, perfect for retreating from state affairs and for frolicking with his mistress in a snowy-white fairy-tale palace (closed for renovation). For added romance, he brought in a flock of peacocks that gave the island its name; you'll find the eponymous birds strutting their stuff to this day.
Even with the palace closed, Pfaueninsel makes for a lovely excursion. A standout among the smattering of other buildings is the Meierei, a dairy farm in the shape of a ruined Gothic monastery at the island’s northern end.
The island is a nature preserve, so no smoking, cycling or swimming. There are no cafes or restaurants but picnicking is allowed. The island is about 4km northwest of the Wannsee S-Bahn station, from where bus 218 goes to the ferry dock several times hourly.