"Tortuous" Or "Torturous"?
The travellers took a tortuous route.
Whereas torturous means ‘involving or causing torture’, as in:
They had a torturous five days of fitness training.
However, in extended senses tortuous is used to mean ‘excessively lengthy and complex’ and hence may become indistinguishable from torturous: something which is tortuous is often also torturous, as in:
It was a tortuous piece of bureaucratic language.
Their way had been tortuous and very difficult.
This overlap in sense means that tortuous is sometimes used interchangeably with torturous.