It means very difficult, which causes great difficulty. That causes torture. It also means that it is zigzag, wavy, sinuous, having curves. Crooked, tangled. Difficult.
He says roads sale making them difficult travel
TORTUOUS: 1. CALVARY, IMMOLATION.EMOTIONAL STATE AFFECTED BY DISTRESS, RESENTMENT, PENALTIES.TORMENTO.2. THAT HAS MANY CURVES.