Between spring and early autumn bats begin emerging from their roosts to feed around dusk, particularly around water, and return to their roost just before dawn.
Because they attract insects, street lights, lakes, rivers and treetops are a favourite hunting spot for urban bats. These animals are very true to location and often return to the same hunting grounds repeatedly, so if you find them once, the odds are you can see them there again.
Those willing to stay up all night, or wake up before dawn, could be lucky enough to see the early morning swarming that happens as bats return to disappear into their roosts. Bunkers, tree hollows and other known roosting spots are a great place to look for this.
Anyone interested in taking a closer look at the mysterious creatures can also visit bat cellar in the Spandau Citadel, open daily from noon to 5 pm.
All you need is a comfortable place to recline and your eyes to find bats on the hunt. For spotting water bats, experts also recommend putting a red filter on a torch (flashlight) and shining it across the surface. The red light helps highlight their movements but won't disturb the animals.
Committed bat watchers can purchase or build a device called a bat detector which locates their echolocation ultrasound signals to frequencies that can be heard by humans. Some young people however, may be able to hear lower-frequency bat calls.