The Royal Botanic Gardens at Kew, west London

Grey's Monument:  to Charles Grey, 2nd Earl Grey built in 1838 in the centre of Newcastle upon Tyne, consists of a statue of Lord Grey standing atop a 130-foot-high (40 m) column.[i]

[i] https://en.wikipedia.org/wiki/Grey%27s_Monument
http://www.picturesofgateshead.co.uk/engravings_newcastle2/

On the south bank of the Clyde west of Glasgow

A village on the Scottish side of the border with England famous as a destination for elopements. English law stated that if both parties to a marriage were not at least 21 years old, then parental consent was required. Under Scottish Law, it was possible for boys to marry at 14 and girls at 12 years old without parental consent. The village blacksmith was empowered to officiate at weddings.

Ref: http://en.wikipedia.org/wiki/Gretna_Green

The name by which people living around Birmingham, Wolverhampton and the Black Country  would have referred to Wolverhampton

West of London. Site of Harrow private boys school.

A port on the east coast of England, approximately 130km (80 miles) north-east of London. It was the terminus of a branch of the Great Eastern Railway and served ferries crossing the North Sea.

Reference:
https://en.wikipedia.org/wiki/Harwich_Town_railway_station (accessed 19May21)

Location not identified. Presumably on the on the Glasgow and South-western railway line.

A River boat pier next to Hungerford bridge across the Thames in central London. Now called Embankment Pier

Hungerford Pier c1880

A town at the head of Loch Fyne (see map)

An area of north London. It was a village known for its market gardens that provided food for London. It was not subsumed by London until the early 19th century.

A district on the South bank of the river Thames upstream from central London. The site of the Exotic Gardens at Kew Park (established 1779) which in 1840 became the Royal Botanical Gardens.

Now called Dun Laoghaire

A small town in central Wales. It was a station on the Llanidloes & Newton Railway - the first in Mid Wales

 Llandysul: A market town some 30km by road from Aberteifi (Cardigan) and 25km north of (Carmarthen)

Llanybydder, a market town in the Teifi Valley,  west Wales.

Loch Fyne : An arm of the sea (sea loch) off the Firth of Clyde and forms part of the coast of the Cowal peninsula. Located on the west coast of Argyll and Bute, Scotland.

Reference:
https://en.wikipedia.org/wiki/Loch_Fyne accessed 08Oct2019