This has self sown and is growing behind the shed.
We have been growing pumpkins and courgettes / zucchini, but this is neither
Do you have any idea what it is?
Is it a pumpkin / courgette hybrid?
or is it some other variety of cucurbita?
Members of the Cucurbita family are notoriously promiscuous so it could easily be a cross from anything you have grown previously, especially if it has self seeded. Is that a variation in leaf colour or mildew? As LR has said, try one or two as courgettes, and if not so nice, let them grow out and try harvesting when they are ripe.
those speckly leaves indicate courgette, but could be anything with cucurbits.
The fruit look like spaghetti squash. That is a cucurbita pepo the same as zucchini, gem squash, and some pumpkins. They all cross with each other really easily so if you have had these in your garden at the same time you get weird offspring!
Beware, when trying them as courgettes, that they do not have a bitter flavour. This might be a natural (so that means it is good, right???) poison (which does make them very, very nasty), which has mostly been bred out of cucurbits but sometimes occurs. Cooking and flavouring makes it possible to eat them if they have this poison, but it will still make your gut very unhappy
If you had two reasonably good representatives of Cucurbita pepo growinglast year, and they crossed, you have a good chance of getting something good, even though it might not resemble one or the other of the parents.
The bitterness would still be several generations removed.
But then, there's always the genetic throw back,,,,,
Mum picked the largest fruit and we cut it open - there was a strong "melon" smell, but no-one was game to try eating it as the seeds look like they have not yet finished developing, so it probably isn't ripe yet.
We'll see what the other fruits are like once they ripen...
(The attached photos have been taken both with and without a flash)