Jura's nearest city is Glasgow.
Direct routes to Jura
A seasonal passenger ferry now runs from Tayvallich on the mainland around 2.5 hours drive from Glasgow to Craighouse on Jura, taking around 45 mins to an hour to complete the crossing and linking up with buses to Lochgilphead. The ferry runs from Easter to the end of September with two crossings a day 6 days a week, including weekends.
In addition, a few of licensed boat owners provide a private water taxi service from the Tayvallich and Crinan area who will drop you at various points on the island.
Getting to Jura via Islay
Caledonian MacBrayne CalMac runs a number of vehicle ferries per day between Kennacraig on the Mull of Kintyre around 2.5 - 3 hours drive from Glasgow to Port Askaig or Port Ellen on Islay. Vehicle bookings should be made in advance as these sailings are often fully booked. The crossing takes 2 hours to Port Askaig and 2 hours and 10 minutes to Port Ellen.
Flybe operates two return flights per day one on Sundays between Glasgow International Airport and Islay - public transport runs from the airport to Port Askaig.
A small car ferry operates across the Sound of Islay between Port Askaig on Islay and Feolin Ferry on Jura. The ferry runs roughly hourly from 6AM to 6:30PM every day (http://www.islayinfo.com/...) though Sundays have reduced hours. The ferry often leaves up to 15 minutes before the scheduled time, so get there early! From Feolin Ferry it is 8 miles to the island's main settlement, Craighouse.