I always find the word Teesside strange when I'm approaching Middlesbrough. Are there many other places with consecutive double letters in their names?

I don't how many others there are, but Woolloongabba is one of them. It is a suburb of Brisbane in Queensland, Australia, and home to the cricket ground known as the Gabba, owing the Australian habit of apparently abbreviating words wherever possible.

https://kangaroopointhistory.com.au/places/the-gabba-woolloongabba-cricket-ground/

https://www.espncricinfo.com/cricket-grounds/brisbane-cricket-ground-woolloongabba-brisbane-56336

https://www.thecricketer.com/gabba.html

Woolloomooloo is a suburb here in Sydney.
https://en.wikipedia.org/wiki/Woolloomooloo

It's 1½ miles (2.4km) from the Sydney Cricket Ground
https://tinyurl.com/wmloo-scg
and 1.2 miles (1.9km) from the Sydney Opera House
https://tinyurl.com/wmloo-soh

Wootton Bassett can lay claim to quite a few double letters. This Wiltshire town was given the 'Royal' prefix in 2011 as its proximity to the RAF base at Lyneham meant that servicemen and women killed in war passed through the town when they were repatriated. The townspeople, led by the Royal British Legion, made a point of point of lining the pavements to provide a guard of honour particularly during the wars in Afghanistan and Iraq.

https://www.historic-uk.com/HistoryMagazine/DestinationsUK/Royal-Wootton-Bassett/

https://www.visitwiltshire.co.uk/towns-and-villages/royal-wootton-bassett-p462573