Are there nonstop flights from Kayseri (ASR) to Hannover (HAJ)?

Yes. SunExpress, Corendon Airlines fly this route. Flight time is about 3h 26m.

What is the fastest connection from Kayseri (ASR) to Hannover (HAJ)?

via Vienna ≈ 3h 58m, via Istanbul ≈ 3h 59m, via Istanbul ≈ 3h 59m (estimated flying time, excluding layovers).

from 15,000 ANA miles (economy, one way, based on the published award charts).

Kayseri Erkilet International Airport (ASR) to Hannover Airport (HAJ)・2,497 km

Nonstop flights available (2 airlines). Flight time about 3h 26m. Nonstop return flights also operate.

With milesANA 15,000 miles+ (via IST)Economy, one way, estimate. Tap a connection for miles by cabin.

9 one-stop options, sorted by estimated flying time. Tap one to see the airlines on each leg and booking links.

Times are estimated from distance. Check schedules, frequency and availability with the airline or a booking site.