The calculated distance (air line) between Sant Martí and Horta-Guinardó is approximately 2 miles respectively 3 kilometers.
By car or train, the actual journey to Horta-Guinardó is certainly longer, as only the direct route (as the crow flies) between Sant Martí and Horta-Guinardó has been calculated here.
Air line (approximately)
3 kilometers
1 nautical miles