The calculated distance (air line) between Siilinjärvi and Jyväskylä is approximately 85 miles respectively 137 kilometers.
By car or train, the actual journey to Jyväskylä is certainly longer, as only the direct route (as the crow flies) between Siilinjärvi and Jyväskylä has been calculated here.
Air line (approximately)
137 kilometers
74 nautical miles