Originally built in Byzantine times but restored in the 1790s by İzzet Mehmet Paşa, İncekaya ('thin rock') Aqueduct is just over 7km north of Safranbolu. You can't walk across it due to safety concerns, but just before the aqueduct an entrance leads down into the Tokatlı Canyon where there are excellent views looking back up to the arched stone structure from the wooden walkway.
Nearby is the highly popular Crystal Terrace – a glass viewing platform looking over the gorge, but not the aqueduct.
A taxi from Safranbolu costs ₺60 return including waiting time.