In reply to Lozzypoz123:
As others have pointed out above, if indoor and sport climbing are your thing, then you are going to be left sorely wanting if you move to Cornwall but, if you are prepared to embrace the wealth of trad climbing (from short, fierce test pieces, to full on adventure on collapsing cliffs, where survival is more important than an Instagram post), then you will be rewarded with a lifetime's worth of climbing.
Some things to consider:
Cornwall is a rural county. It does not have all the modern conveniences that you will be used to having in London. For a climber looking to get to the crags, having the ability to drive and owning your own car is far more important than knowing how to read a bus timetable.
Also, the road network makes even the shortest journey take longer than expected, especially during emmet season and the harvest. Be prepared to have to drive at least an hour or more to any climbing venue from Falmouth.
The main A30 is currently undergoing an upgrade between the two Truro roundabouts, which has increased any journey time up and down the county. This isn't due to completed until the end of 2023. (Although it won't affect your journey west from Falmouth).
Despite what someone mentioned above, it is possible to climb all year round. It is not uncommon to be climbing on the Lizard and the south coast of Penwith, in winter, in a T-shirt.
There is also extensive bouldering. Tom Last (above) is the person to speak to.
To be fair to the guys at Granite Planet, they were the first 'modern' commercial indoor climbing wall in Cornwall. They have been in existence for at least 15 years, but they have been under the threat of losing their venue due to the expansion of the university. They have been waiting for the landlord to find them another suitable venue for a number of years, but this hasn't happened and, as such, aren't prepared to invest further in the place if they are going to lose it.
If you are looking to build a wall/gym, you definitely will need to do your homework. Property down here isn't cheap and is comparable to London prices. The majority of local folk don't earn anything near what folk in other parts of the country earn (even less in the current situation).
Population density is considerably less than places like London, Bristol etc and there aren't any big population centres nearby (eg N Wales benefits from being surrounded by Liverpool, Manchester and Birmingham...and good transport links). To get a feel for what it's like, you'll have to speak to the folk at The Tide. They opened in 2019, I think.
Best of luck.
Post edited at 09:49