The largest and highest of Šibenik's land fortresses, St John's crowns Tanaja hill at 115 metres above the sea. It is a star-shaped Venetian work of the 1640s, designed to lob cannon fire at any Ottoman force trying to come over the ridge. The restoration here is more recent and lighter-touch than Barone or St Michael's; the appeal is the scale and the view rather than polished facilities.
Get here on foot from town in about twenty-five minutes of steady uphill walking, or drive part of the way. In summer the fortress hosts concerts; outside those evenings it is often half-empty, which after the cathedral crowds is exactly the point. Combined fortress tickets include St John's.