Caledonian MacBrayne, generally known as CalMac, operates all main services on the Firth of Clyde and to the Inner and Outer Hebrides, sailing to over 30 west coast destinations. Mainland ports which serve the islands in the west include Oban and Kennacraig in Argyll, and Mallaig and Ullapool in the Highlands. There are also smaller local operators like Western Isles Cruises which provide daily services to locations on the west coast such as Inverie and Tarbet in Loch Nevis from Mallaig.
For CalMac ferries, it's recommended to book tickets in advance wherever possible, although you can normally buy foot passenger tickets on the day of travel. If planning on making multiple ferry journeys, you can consider purchasing an Island Hopping ticket which combines multiple journeys.
Always check the journey information before you travel, for details on baggage allowance, checking in times and delays or cancellations due to weather conditions.
CalMac also runs a regular service between Dunoon and Gourock, which can be combined with a train ticket from Glasgow Central and only takes an hour and a half in total. Local operator Western Ferries (Clyde) also operates a daily service between Gourock and Dunoon which sets sail every 15 minutes during peak times.
If you're planning a trip to the Small Isles, Arisaig Marina offers scheduled trips. There are several crossings each week to the islands of Eigg & Muck, with additional sailings to Rum, Canna and Loch Coruisk on select Sundays throughout the summer months. Day trippers to these incredible islands have plenty of time on the island of their choice to explore the landscape, observe wildlife or just soak up the atmosphere of island life.