Now, if you're going to go to one of many of Scotland's islands or peninsulas - but, asides from flying, you're not sure how to get there - then this post is for you.
These are the main ferry operators:
Caledonian MacBrayne (CalMac): https://www.calmac.co.uk/
Western Ferries: http://www.western-ferries.co.uk/
Argyll Ferries: http://www.argyllferries.co.uk/
Kilcreggan Ferry: http://www.spt.co.uk/kilcreggan-ferry/
NorthLink Ferries: http://www.northlinkferries.co.uk/
Pentland Ferries: http://www.pentlandferries.co.uk/
John o' Groats Ferries: http://www.jogferry.co.uk/
Here are the trains:https://www.scotrail.co.uk/Arran, Bute, Great Cumbrae, Rosneath and Cowal
In the Firth of Clyde lie the islands of Arran, Bute and Great Cumbrae. These can all be accessed by CalMac car ferry journeys.
The main route to Arran is via ferry from Ardrossan. There are two train services from Glasgow Central per hour; one stops in the south of the town, continuing to Largs, while the other runs through Ardrossan Town station and meets the ferry at a station at Ardrossan Harbour.
On Sundays, there are only five trains a day on the harbour route.
CalMac also operate a ferry link between Lochranza, in the north of Arran, and Kintyre - it runs to Claonaig in summer and to Tarbert in winter. Handy for island hopping! The ferry is fairly frequent to Claonaig in summer, but only once-daily to Tarbert in winter.
The ferry to Great Cumbrae - often just called Cumbrae - departs from Largs. Largs is accessible by train from Glasgow Central - the services are usually hourly and call at major town such as Paisley, Johnstone, Saltcoats and Ardrossan en route.
To reach Bute, take the train to Wemyss Bay (pronounced 'Weems Bay') on the Inverclyde Line. The service passes through Paisley, Bishopton, Port Glasgow and Inverkip on its way to the town. The station at Wemyss Bay is an architectural wonder - do take a few minutes to pause and look around, if you can. The train service usually operates hourly. The station at Wemyss Bay is also right next to the ferry terminal, from which the MV Argyle or MV Bute will waft you over to Rothesay, the main town on Bute.
A short CalMac ferry service also connects Rhubodach, in the north of the isle, across the 400 yard Kyles of Bute to Colintraive in Cowal.
Western Ferries run a car ferry between McInroy's Point in Ayrshire and Hunter's Quay in Cowal.
There are usually five trains per hour between Glasgow Central and Gourock, via Paisley, Bishopton, Port Glasgow and Greenock. From Gourock station, McGills operate bus services 901 and 907 to McInroy's Point to meet with the Western Ferries ferry service to Dunoon, the main town in the Cowal peninsula. While route 901 continues down the Ayrshire coast to Largs, route 907 travels on the ferry to Hunter's Quay before continuing on to Dunoon. The 901 and 907 both start in Glasgow.
Argyll Ferries run a passenger-only ferry service between the centre of Gourock and the centre of Dunoon. The terminal at Gourock is close to the rail station.
From Gourock ferry terminal, Clydelink run an SPT passenger ferry service to Kilcreggan on the Rosneath peninsula. This service runs fairly frequently - though not on Sundays - and connects at Kilcreggan with fairly regular bus services to the villages of Coulport, Cove, Rosneath, Garelochhead and Helensburgh - the latter two of which have railway stations. This provides another route to the peninsula - you can take the train from Glasgow Queen Street to Garelochhead, and change onto the bus there.