North of Turkey Run in Fountain County is Portland Arch Nature Preserve. It is a unique feature for Indiana. The creek has undercut a stone ridge, forming an archway. For more things to see, visit my Fountain County page, a.k.a. Veedersburg, Indiana.
The east end of the park is where the narrows covered bridge still stands. It's actually a part of the park trail system. It's the connection between trails #4 & 8 on the north side and trails #1 & 2 on the south side of Sugar Creek. Built in 1882, it's in need of some repairs.
It has been replaced by a concrete arch bridge in the 1960's, which is still used by traffic.
For more images, see my Turkey Run travelogue on the Narrows and/or my Rockville travelogue on the Narrows.
At the west end of the park (Cox Ford Road) is an 1905 Burr Arch Covered Bridge. It is on raised abutments to keep it above the flood waters in the spring. Additional height allows trees with roots and limbs sticking out to pass without damaging the bridge.
If you have the time, see Rockville and some of the other 37 covered bridges in Parke County.