Learn Finnish: Menimme metsään pimeydestä huolimatta. - We went into the forest despite the darkness.

The word huolimatta (despite) is an adposition of concession that requires its companion noun to be in the elative case. Whenever you use huolimatta, the noun it modifies must take the -sta/-stä ending.

What is the base form of pimeydestä, and why is there a d in the middle?

The base noun is pimeys (darkness). Nouns ending in -ys form their stem with -yte- (making pimeyte-). However, adding the elative ending -stä closes the final syllable. This triggers consonant gradation, weakening the t to a d, which results in the final form pimeydestä.

Can huolimatta be placed before the noun instead of after it?

Yes, huolimatta is very flexible. It can act as a postposition (pimeydestä huolimatta) or a preposition (huolimatta pimeydestä). Both orders take the elative case and mean exactly the same thing, though putting it after the noun is slightly more common in everyday Finnish.

As a quick refresher, why do we say metsään instead of metsässä?