It's in Marleybone, you have to go to Digmore Station, in the back, where the docks are. Kensington Park is the last dock on on the left. It's a huge instance that you can't do alone. They recommend the player and 3 friends to do it.
Even though your team is full, I'd gladly help if one drops out. I'm level 72 life wizard. Trust me, you'll need a life on your team. :) I've done Kensington Park, it's hard. It was hard for level 80 friend. So good luck. -Kristen Daisyleaf :)