Bagh-e Fin is the garden people mean when they talk about Persian paradise gardens, and it sits at the southwestern edge of Kashan, right where the desert gives up and the mountains begin. The reason it exists is a spring. Water rises at the foot of the hills and has done for thousands of years, and the Safavid shah Abbas I turned it into a walled garden around the end of the sixteenth century, with straight channels, tall cypresses, fountains and a pavilion at the top of the slope, all organised around the idea that water in a dry land is a luxury worth building a palace for.
The gardeners did something clever. The spring feeds the pools by gravity alone, no pumps, so the fountains run because the ground tilts. On a hot afternoon the sound of it alone drops the temperature a couple of degrees. The garden is part of the UNESCO group of Persian Gardens, listed in 2011.
It also has a darker footnote. In 1852 Amir Kabir, the reforming chief minister who had tried to modernise Iran under the young Naser al-Din Shah, was murdered in the bathhouse here on royal orders. Visitors are shown the room, and the story gives the cool tiled halls an odd weight for a place so pretty.
Practically, Kashan is a city of several hundred thousand people, so fuel, food and hotels are easy, and you will not be stuck. The ride here from the desert side is long and flat, with the road entering town through an unremarkable ring of workshops before the old quarter opens up. Park near the garden entrance and go in early or late, because midday sun on bare paths is fierce and tour buses arrive in waves in spring.
Leave time for the old houses in the centre, built by rich carpet and rosewater merchants, with deep courtyards and wind-towers, and for a tea in a courtyard cafe. October and April are the best months, when the garden is green, the air is mild and snow is still on the far mountains.