Do take a trip on this cable car, it goes very slowly and sedately high over the river thames at Greenwich. The staff are very helpful and the views are fabulous and you learn a lot about this regenerated part of London. Use your oyster card to pay by touching in and out as this is the easiest and cheapest way of paying. You can do a single one-way trip, or stay on and get a round trip.
Great fun and highly recommended 🙂