Tamdhu :

Tamdhu = Means Litle black hill. 
The Principal Speyside product among the bottled single malts in the Highland Distilleries range. A mild, urbane whisky, learning towards malty sweetness. 
The distillery is in the heart of Speyside, between Knockando and Cardhu. It was founded in 1896 and largely rebuilt in the 1970's. The water comes from the Tamdhu burn, witch flows through woodland into the Spey. Thamdu has a impeccably well kept, and has its own touches of tradition, notably its enthusiasm for wooden fermenting vessels. 
The whisky is becoming better known as a bottled single malt and is a component of The Famous Grouse blend. 
At barrel proof, it has performed especially well in Scotch Malt Whisky Society bottlings.

Remarks from the book 'The Scottish collection' Classic Malts by Carol P. Shaw :
Tasting notes : A good, light-to-medium Speyside malt, which is slightly peaty but with a delicate sweetness and a logn, subtle finish. / Taste rating = 3
Highland Distilleries bought this distillery shortly after it opened in 1897 and have owned it ever since. It was extensively refurbished in the 1970's and is now one of the most modern distilleries on Speyside. Set in the Spey vally, Thamdu used to favour the hyphenated Glenlivet suffix, but this has been dropped in recent years. As well as its appearance as a single malt, Thamdhu features in The Famous Grouse blend, owned by Highland's subsidiary, Matthew Gloag & Son.

From the Whisky pilot by Uniqum Systems :
Founded in 1896 by a group of whisky blenders, Tamdhu distillery was, like several others, located along the Strathspey railway line which by then played a major role in the whisky industry. A few years after it was built it was taken over by Highland Distillers. It was closed from 1927-47, but extended in 1972 from two to four stills and again to six stills in 1975. A feature is Tamdhu's Saladin Maltings which have been largely rebuilt. The old Knockando railway station was converted into an attractive visitors centre and reception.
Tamdhu does not have the traditional pagoda heads atop its kilns, having instead a short, square concrete chimney.
Situated on the banks of the River Spey south of the B9102 between Knockando and Archiestown.

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Source www.bbr.com :

Tamdhu Distillery, Speyside

Tamdhu in Speyside was founded in 1896 and was bought by Highland Distilleries Co Ltd. The distillery was designed by the celebrated architect Charles Doig of Elgin. The distillery did quite well for a number of years before a decline starting in the 1910’s, due to the falling interest in whisky.

However, post-war Tamdhu was very well-regarded by whisky blenders, and the distillery’s trade was restored in 1947. In 1975 the number of stills was increased to 6, and the whisky was launched as a Tamdhu single malt.

The distillery was mothballed under the Edrington Group in 2010, which means that blends such as Famous Grouse and Cutty Sark will have to do without its softer malt feel.

Tamdhu Fine Single Malt Scotch

Tamdhu kommer fra Speyside, som uden tvivl er et af de Fineste produktionsområder.

Tamdhu er det eneste destilleri i Speyside, der malter sin byg selv og dermed har fuld kontrol over hele produktionsprocessen.

Tamdhu er en single Malt uden aldersangivelse.
Tamdhu er kvalitetsmæssigt et fantastisk godt bud i kategorien single Malts uden aldersangivelse.

Single Malt er sum bekendt den eneste officielle og tilladte betegnelse for Maltwhisky fra et enkelt destilleri.