The Muntapa Tunnel is a tunnel for an old railway branch line from Oakey through to Cooyar that operated between 1913 and 1964.
The tunnel is Queensland’s longest straight railway tunnel at 287m long, and the only tunnel in Australia that crossed between the inland and coastal sides of the Great Dividing Range, connecting two different water catchment areas.
Railway branch lines played an important role in pioneering of regional area providing support to small-scale agriculture. With the improvement of roads and faster road transport, branch lines became redundant and closed.
The tunnel took some 13 months to bore through, with families of the workers living on site at Muntapa. The government set up a school to educate their children on site, one of few buildings with most living in tents.
The tunnel interior is formed with concrete, first used in the 1880s when it was found to be more economical than brick or masonry. 1912 was above the entrance at one end, but with wear, this appears as 912 now.
A park is above the tunnel, with picnic tables, BBQs and toilets. There are some information panels with details about the camp while the tunnel was being built. As the camp were mostly tents, few relics remain.
The remains of a bakehouse are evident by a pile of stones cemented together. The Muntapa Camp School, a small building with the top half of the walls made from canvas. The canvas is pegged up to allow a breeze to flow through. The stumps are all that remains of the school.
From the park, both ends of the tunnel can be accessed. Heading to the left (passed the school and bakehouse) leads to the Cooyar end, with stairs leading down the steep cutting.
A brown sign in the park points to the Oakey end with a flatter track to the beginning of the cutting approaching the tunnel, then walking up the cutting to the tunnel entrance.
Alternatively, the road passed the park leads to the start of the cutting for the Oakey end. For those who don’t or can’t walk too far, there is some parking space available off the road.
Both entrances are gated, blocking access into the centre of the tunnel. The gates are not right at the entrance, however, so you can walk in far enough that it is dark, especially from the Oakey end as the gate is set further in.
The gates are to protect the bent-wing bats that use the tunnel for roosting and breeding. The Cooyar end was distinctly smellier, I didn’t notice a breeze through the tunnel but must have been enough to send the smell of bats in that direction.
The Boolboonda Tunnel 
near Gin Gin is open to walk all the way through, even though it has microbats inside. It is shorter at 192m long, but it is the longest unsupported tunnel in Queensland.
From the park near the parking area, there is a viewing platform overlooking the entrance at the Oakey end.