Walking around this area at night comes with serious danger.
Literal
Night this area [obj-を] walk-[nom-のは] big danger [subj-が] accompanies.
伴う ('accompany, come with, be attached to') is a formal verb for something bringing along other things as consequences. 危険が伴う ('danger accompanies (it)') is the standard phrase for 'there is danger involved.' Formal/advisory register.