The upper leg circumference is the measurement around your leg, near the top of your leg.
You should measure this a bit below your crotch, refer to the illustration for guidance. Zorg dat de lintmeter horizontaal (parallel met de vloer) blijft terwijl je deze maat neemt.
This measurements is also used as a vertical reference to determine the vertical space in which to draft the seat/crotch of trousers. As such, the vertical location of this measurement is important.