This series of lovely waterfalls and tranquil pools trails through the O'heo Gulch and flows into the ocean nearby. The Pipiwai Streams feeds these falls and other numerous pools...a lot more than just seven. However, the easiest to reach and the nicest pools are located near the shoreline.
The Drive to Hana is beautiful in itself with lots of waterfalls and spectacular views to witness. Make sure you plan this as an all day trip. It's only about 40 miles, but you won't get a chance to drive above 10-15mph in most cases due to the hazardous roadway....very winding and narrow!
The Pipiwai Trail, above the Seven Sacred Pools, is one of the best hikes on Maui. It's about 4 miles roundtrip. It takes 2 1/2 - 5 hours to hike, depending on how much nature loving you do. There's several great waterfalls along the route with the final destination fall being Waimoku Falls, falling 400-feet down a sheer lava rock wall.