What is a good exercise to work out the upper back of your legs?

Going on vacation soon and want to make sure every part of my body gets toned. The only muscle group I can really seem to get going is the back upper part of my leg (near your butt lol). Does anyone know any good exercises for that?

Deadlift. You can use dumbbells or a straight bar. Slight bend in your knee, feet about 3 inches apart. Back straight and flat and bend down until you are at about parallel to the floor (more or less depending on your flexibility). Remember to keep your back flat, don’t round your shoulders or hunch) keep your shoulder blades squeezed together. Keep the bar or dumbbells close to your thighs/shins on the way down and back up. 3 sets or 15 to 20 reps at a medium weight should do it.
Also, step ups. I prefer dumbbells. At your sides in front of a weight bench. Step up with your right leg and then "step up". Touch your toe on your left leg to the side of the bench (helps you stabilize) then ease yourself back down. Do this 10 times on each leg for 3 sets. This time at a lower to medium weight you can handle fairly easily at first until you get the hang of it. Some people are quite unstable initially.