When you travel to Islay by car there are several possible routes to choose from if you take for example Glasgow as the starting point of your journey. When you come from further away you might even split your journey in half, making your trip by car on one day and leave for Islay the next day. This would of course require you to find accommodation somewhere in Argyll, more about that at the bottom of this page.
Total travel time 2.5 to 4 hours, distance by car approx. 170 km.
This is the most obvious route and a very fine drive through Argyll's beautiful countryside. Coming from Glasgow you take the M8 and cross the Clyde over the Erskine Bridge. From there take the A82 through Dumbarton and follow the road along Loch Lomond untill you reach Tarbet. Here you take the A83 to Inveraray/Campbeltown enjoying the nice views and the possibility for a break at Rest and be Thankful. Follow the A83 south and soon you drive along Loch Fyne, on your left, and reach the picturesque town of Inveraray, which can be quite busy at times. When you have time try to visit Inveraray Castle (picture) and discover that there is a lot of interesting information about Islay as well. Other visitor attractions are Inveraray Jail or Loch Fyne whiskies, they have a very good selection of malts. Continue the journey south on the a83 to Lochgilphead. Five miles outside Inveraray is a little outdoor museum called Auchindrain Museum of Country Life, which is another interesting visitor attraction, providing you have the time. Now it's another 24 miles to Lochgilphead and another 14 to reach Tarbert, which is a very nice little town and has a picturesque port. From Tarbert follow the A83 for six km untill you reach the Kennacraig ferry terminal on your right.
Total travel time 3 to 5 hours. Total distance by car approx. 90 km and 50 minutes on two ferries.
This route is a lot shorter considering the distance but requires two ferry crossings, one from Gourock to Dunoon on the Cowal peninsula. You're either lucky and arrive just in time for the ferry or in the worst case you have to wait for the ferry to return which could take about 20 - 60 minutes for each ferry. In Glasgow take the M8/A8 to Greenock and then the A770 to Gourock. Here you take the ferry, a 30 minute crossing, to Dunoon. From Dunoon take the A885/B836/A886 and A8003 to Portavadie. Here you can take a ferry, a 20 minute crossing, to Tarbert. From Tarbert follow the A83 for six km untill you reach the Kennacraig ferry terminal on your right.
Total travel time 3 to 5 hours. Total distance by car approx. 125 km and 1.5 hour on two ferries.
Another alternative and a very beautiful route as well. You might want to spend a day on Arran instead of using it only as a through route, but if you don't have the time here is how you drive. Take the M8 in Glasgow and follow the A737 south at Paisley and next take the A78 to Ardrossan. Here you can take the ferry to Brodick which takes about an hour. From Brodick you can take the A841 to Lochranza which is 14 miles. At Lochranza take the ferry to Claonaig, a 30 minute trip, and after seven km on the B8001 you reach Kennacraig. I would personally recommend to stay for a day on Arran. Arran has a lot to offer and is worth a proper visit. Leaving the next day on an early ferry from Lochranza and you're in time to get the one o'clock ferry at Kennacraig.
I personally used to travel to Tarbert first before we moved to Islay and take the ferry to Islay the following day, holiday starts when you leave home and there is so much to discover in Scotland. There are a few good B&B's in and near Tarbert. For addresses visit www.tarbertlochfyne.com. If camping is your thing you might consider driving to Rhunahaorine Point, there you will find a very clean and good campsite with good facilities. Maybe a bit unsheltered but only meters away from the beach.
Some Important advice
To get the latest info on Ferry cancellations or disruptions make sure to read How to check if the ferry to Islay is sailing. Valuable advice which might help you.
Have a safe journey!