I am trying to arrange a trip to Grudziadz, on the banks of the Vistula River to the south of Gdansk, to visit the castle in which my Grandfather was imprisoned during the First World War. Do you know of any operators that cover this region of Poland? Robert Holland, Birmingham

Sunday Times travel expert, Richard Green, responds: Poland is chockablock with impressive castles; from bluff medieval fortresses to fancy renaissance confections; and several of them house atmospheric hotels too.

However, while Grudziadz is in the heart of Pomeranian castle country, there’s very little left of its fortress, save for some of the walls and a ruined tower. Like the other defensive settlements in the area, the Teutonic Knights built it when they returned from their Crusade to the Holy Lands. Once that campaign fizzled, they traipsed back to Europe as especially well armed refugees, and looked for somewhere new to subdue. Unluckily, this part of Poland suited them nicely.

The town itself is a 90-minute drive south of Gdansk and while it isn’t on the tourist trail, it does have attractive city walls, some giant siege-busting granaries, and is the home to a distinguished regiment of the Polish cavalry.

Go Poland (0870 991 7380) specialises in tailor made trips to Poland and can arrange a day tour from £70pp (based on two people), with a local guide picking you up from your hotel in Gdansk, and then sightseeing to Grudziadz and around.

You could also take in the spectacular red-stone castle at Malbork. It was built as the new HQ for the Knights and is extremely well preserved. And a little south of Grudziadz is the complete Gothic town centre of Torun, which is the birthplace of Nicolaus Copernicus, with an exquisite town square and a museum in Copernicus’ former home.

Go Poland offers group tours too. Or try Polish Regency Tours (020 89926004), or Fregata Travel (020 7420 7305).

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