pacific beach, mission beach, mission bay, fiesta island length of mission valley and back, bike path to ocean beach, voltaire to nimitz. hit shelter island, harbor island and harbor drive all the way down to the bike path running parallel to hwy 54. do the flattish parts of sunnyside/bonita and head back west to the bay. south along the west side of the 5 fwy all the way past the salt factory to the true start/end of the dedicated bayshore bikeway. around the bottom of the bay and all the way to coronado and ride around it before looping back down south, curving around the bottom of the bay and heading north back towards dtown sd. by the time you reach mission bay area again, you’ll be around 90 miles. your loops around fiesta island or riding around mission bay again will get you there.