Oh what fun we had landing our fish dinner right off the bridge you are showing by Robbie's. We spent a week at the Hampton Inn at MM84 and hit most of the bridges to the south. The Tea Table Bridge (MM79) is the closest and is excellent, as there is lots of parking around the landfill. The Channel 5 Bridge at MM71 has parking on the south end. The Channel 2 Bridge at MM73 has parking on both ends, plus you can go down on the Shoreline to fish here.
The long key bridge is a bit further down at mile marker 65. This is one of the top places because of the water flow. Florida Sportsmen Fishing TV Show did a whole episode on the fishing by the long key bridge. Get your bait at Bud and Mary's and they will tell you what to use.
You can watch the tv show Reelin in the Keys on the hotel's local channels. It is great and always gets us pumped to fish. The key to bridge fishing is picking out one to three hours when the weather is nice, so you will be cozy and cool.