Pengwern

Whittington Castle stands in the village of Whittington in northern Shropshire, close to the Welsh border and the old fort of Old Oswestry. It began as a motte-and-bailey castle and was rebuilt in the 13th century, with buildings along a curtain wall, five towers on a raised platform, a moat and an outer gatehouse or barbican.

Tip: Look for the viewing mound in the centre of the site, which may be the oldest of its kind found in England.

Pontcysyllte Aqueduct carries the Llangollen Canal across the River Dee in the Vale of Llangollen. Designed by Thomas Telford and William Jessop, it is a cast iron trough held 127 ft (39 m) above the river on eighteen hollow masonry piers, with 19 arched spans. It is 336 yards (307 m) long and about 12 feet wide.

Plas Newydd in Llangollen was the home of Lady Eleanor Butler and Sarah Ponsonby, two Irish ladies who eloped and set up house together in the late 18th century. It began as a five-roomed stone cottage and was enlarged with many Gothic features. It is now a museum.

Tip: Look closely at the outside of the house as well as the rooms, since the patchwork of reclaimed oak carvings is its most unusual feature.

Shrewsbury Castle is a Grade I listed red sandstone castle standing on a hill in the neck of the River Severn's meander. Ordered by William I around 1067, it was extended as a base for operations into Wales. Parts of the original medieval structure remain, including the inner bailey.

Tip: Access to the castle grounds is free, so you can look around them even if you don't go into the museum.

Erddig is a late 17th-century country house near Wrexham, saved from dereliction in the 1970s. The Yorke family had an unusual relationship with their servants and commemorated them in portraits and poems, and the servants' quarters and estate workshops survive well. Outbuildings include the Joiners' Workshop, Smithy, Sawmill and Stables, and the house holds a fine collection of 17th-century furniture.

Tip: Postcodes aren't always recognised by sat navs, so follow the brown signs on the A525 or A483. Parking is free. Dogs are welcome in the garden and on the estate on a lead, but not in the Hall, Hayloft Restaurant, shop or Wolf's Den (assistance dogs are allowed everywhere). Check the National Trust dog page before you go, as rules can change.

Chirk Castle (Castell y Waun) was built in 1295 by Roger Mortimer de Chirk as part of Edward I's chain of fortresses across north Wales, guarding the entrance to the Ceiriog Valley. It was partly demolished in the English Civil War and then rebuilt, and the Myddelton family bought it in 1593. It is a National Trust property and Grade I listed.

Pitchford Hall is a Grade I listed Tudor country house about six miles from Shrewsbury, built around 1560. Its timber-framed, black-and-white look is striking, and the estate has an orangery and walled garden. Queen Victoria stayed here as a young princess, and during the Second World War the house was chosen as a possible retreat for the royal family.

Tip: Tours of the hall, grounds and treehouse need to be booked in advance through Invitation to View.

The Conwy Valley Railway Museum sits beside Betws-y-Coed railway station, on the site of the old goods yard. The museum building holds a collection of railway artefacts, and the attraction began with a former standard gauge railway carriage, which is a licensed buffet and restaurant car.