Already covered in the beach section are a number of surfing and coasteering options in the area. But if getting in the water isn’t your thing then maybe exploring the coast by boat is. North coast options include
Celtic Warrior, Padstow, Contact Shane Farley, 07970 684339. email celticwarriorpadstow@gmail.com
Scenic Tours and Fishing Trips, Boscastle Harbour, Contact Andy Walton, 07967 787384 / 01208 851660
Cornish Sea Tours, Polzeath 07791 533569
Padstow Sea Life Safaris, Padstow, 01841 521613
The south coast has a wealth of beautiful inlets especially around Falmouth and you can experience these by ferry https://www.cornwalls.co.uk/transport/ferries
or through boat hire https://www.falmouthboathire.co.uk/
The ferries between Mevagissey and Fowey https://www.mevagissey-ferries.co.uk/are a more unusual way to get from one spot to another.