Two bridges over the Forth
This is one of my all-time favourite rides. It follows National Cycle Route 76 for most of the way and takes you clockwise around the River Forth from my home town of Falkirk, over the Kincardine bridge and back via the iconic Forth Road Bridge. Although it's almost 70kms there are very few inclines so it's not too taxing. The scenery is gorgeous, especially on a sunny day, with the lovely seaside villages of Kincardine, Culross, Torryburn, Charlestown and Limekilns on the North side and the interesting Hopetoun Estate with its historic house and Blackness castle on the South side. You also get some fantastic views of the three bridges at North Queensferry - the spectacular new Queensferry crossing (not open for cycling); the old and now retired Forth Road Bridge (which this ride crosses) and the historic Forth Bridge (for rail traffic). There's a real mix of roads too with paved cycle paths; main and side roads and unpaved paths through the grounds of Hopetoun House. Clockwise is my favourite way to do this ride but anti-clockwise is just as interesting with some different views and I may post that here on Kinomap sometime.
If you are ever in the area as a tourist I can recommend spending more time stopping at villages like Culross, Charlestown and Limekilns on the North banks of the Forth and visiting Hopetoun House and Blackness Castle.