This is the site of a former drinking-water reservoir built in 1926 and decommissioned in 2007 after a leak was discovered. The site, which spans 1.5 football fields and once could hold 15 million gallons of water, lay dormant for nearly a decade until the Buffalo Bayou Partnership, with help from the Brown Foundation, decided to reopen it as a public space. Its stunning and sometimes haunting visuals make it among the new must-see attractions in Houston—don’t miss the nearby art installation, Down Periscope, which offers a peek into the cistern from aboveground. Schedule a tour to see it up close—tours last 30 minutes and are held at 3 p.m. every Wednesday, Thursday, and Friday. Reservations required.