Go to Poole Harbour in Dorset, take a small 30 minute ferry ride to Brownsea Island and you have a memorable day out for all the family at your feet.
This small island holds a very different diversity of life than anywhere on mainland England. It isn't all that well known, so it is always pretty quiet and secluded even at the height of the season. From the minute you set foot on the island, you realise there is something different about it. The air is different. Much of the island is covered in coniferous woodland which is home to red deer, and the endangered species, the red squirrel. The smaller grey squirrel on the mainland, chased out the red squirrel which has a more specific diet to the greys, and now they thrive only in some areas of Scotland, and Brownsea. And because the island is so quiet, the squirrels are quite friendly and bold. Peacocks/peahens also roam free on the island. If you take a picnic, you'll find they'll come right up to you to help themselves. (They especially like smoky bacon flavour crisps!)
You are free to roam through much of the woods. Trails are mapped for guidance. Some areas are cordened off as they are being monitored by the National Trust, but there are Trust workers around if you have any questions.
The beaches are gorgeous, and you can see neighbouring, privately-owned islands in close range. (It makes you wish you had the money to own one!) There is a Trust-owned hotel on Brownsea. Booked in advance, visitors may stay, but the John Lewis company have a stake in it and if you are a partner, reduced rates apply.
It is a small but wondeful island that takes you away from the hustle and bustle of the mainland. The only vehicles are the Land Rovers of the National Trust. It is so quiet, peaceful and clean, it is a real surprise that an English island could be so different.