The small locally-owned company DAC Coaches runs a fairly regular bus service (#79) in and out of the village starting from Callington, in Cornwall, with Tavistock, in Devon, as its destination and going via Gunnislake.
There are 15 buses daily Monday to Saturday in both directions andd the journey to/from Tavistock takes about 25 minutes and about the same to/from Callington. Calstock's main bus stop is on the quay, just in front of the Tamar Inn, and the bus also stops at the railway station entrance.
Updated Jul 7, 2011
Website: http://www.daccoaches.co.uk/Serv79.htm
Calstock is on the spectacularly scenic Tamar Valley branch line between Plymouth and Gunnislake and the high-arched viaduct which carries the track across the river here is one of the route's definite highlights.
The view of the village, and the river, from the train is equally impressive from either side and the viaduct itself, as seen from below, with its simple elegance is a marvel of early 1900's engineering and almost makes the village worth a visit in its own right.
The Tamar Valley Line is operated by the First Great Western company and trains run roughly every two hours Monday to Saturday (slightly less frequently on Sundays). From Plymouth to Calstock the journey takes about thirty minutes as the track winds through the Bere Peninsula, first crossing the River Tavy as it heads towards Bere Ferrers then onwards to rejoin the River Tamar after leaving Bere Alston. After Calstock the train continues through the rolling hills of the valley for another four miles to its terminus at Gunnnislake from which it then reverses its journey.
At the time of writing an off-peak day return is under a fiver (£3.15 with my local railcard) and the ticket allows you to stop off wherever you fancy enroute and as a bonus groups of up to four can get a groupsave ticket for the price of two day returns.
Updated Jul 6, 2011
Website: http://www.tourismleafletsonline.com/pdfs/The-Tamar%20valley-Line%20-Leaflet%282%29.pdf
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Calstock is on the spectacularly scenic Tamar Valley branch line between Plymouth and Gunnislake and the high-arched viaduct which carries the track across the...
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From Both Sides Up - A Brief Afternoon Visit

Calstock is a place I passed over (literally) a while back as I took the train up the superbly scenic Tamar Valley line from Plymouth to Gunnislake. The views from the train throughout the journey......
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There isn's a location for Cargreen, a beautiful village on the Cornish bank of the River Tamar, so I've used the nearest available river location - Calstock,
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I've got some interesting experiences in Calstock. I'd love to share with you the 0 tips I've written, the 1 photo uploaded, and 0 travelogues I've created.
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