The Old Quarry Bridge is a bridge that is made out of stone and rocks and is shaped similarly to a viaduct. The bridge only appeared in the sixth season episodes, A Friend in Need and Jack Jumps In, and the Jack and the Sodor Construction Company episodes, Kelly's Windy Day and Percy Helps Out.
Ned once dislodged an important key stone from the bridge and caused the whole bridge to fall apart. Thomas had almost fallen off the bridge, but luckily, Jack quickly came under the bridge and held it up with his crane arm long enough for Thomas to reverse off the bridge to safety.
- In Kelly's Windy Day and Percy Helps Out, the bridge had two railway lines running underneath it.