The entry is free but you are asked to give a 'voluntary' donation. Very reasonable. The gardens are well laid out and it is easy to get around on foot, or, I would think, if you are disabled. (It is on the side of a hill so there are some gradients to be covered.) The restaurant and shop are right in the middle do easy to access from any point and has great views over the river Derwent. The gardens have a good range of the flora and fauna of the island and the displays of the ferns werre excellent. You need about three hours to do the site justice.