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"How To Get There: 1. Head north on Heath St/A502 toward Whitestone Walk. Continue to follow A502. Go through 1 roundabout. 2. Turn right onto N End. Destination will be on the right. It is located just up the hill from Hampstead tube station on the Edgware branch of the Northern Line. The Main entrance onto the gay West Heath is from behind the apartments 'Jack Straws Castle'. Very handy if you can't find it because you just have to ask for the pub. Everyone knows it. Tube: Hampstead underground station. Turn right out of the station and then right again up Heath Street. Continue walking up the street for 5-10 minutes until you get to the big pond. Just past the pond, the road forks at a war memorial, with the former Jack Straw's Castle pub on the left (it is helpfully still labelled JSC). Next to the former pub (now flats) is a little lane running off to the left. Follow the lane down and it turns into a track and then steps down into the heath. Bus: Best routes are 268 (from Finchley Road/Swiss Cottage or Golders Green) or the N5 Night Bus. Both of these stop at Jack Straws Castle (and announce the stop). "
"Cruising Info/ Tips: Usual British thing - look a lot, be uncertain about the whole thing then possibly lose out completely.
Below Jack Straws castle then deep into the woods. Follow the path until you find the infamous and illusive 'fuck tree'. Lots of people ask the way to the fuck tree - if you go down the steps from Jack Straw's Castle, you hit the main path running left-right. Turn right and follow the path (there will be guys hanging around on the path). You will see some buildings high up on the right and the path then bears round to the left. Shortly after this, there is a turning down to the left. Take this and follow the path down into the woods. Eventually, this opens out on the right and there are usually guys heading in that direction. Tends to be very quiet before about 10pm. "
I have no idea if anything helps.