I’ve wangled my day off in lieu in Bratislava next week saved my employer lots of money by taking the late flight.
I have until 9pm at night to get to airport.
Firstly, I think a walk up the hill and explore the abandoned cold war missile base behind the hotel I am staying in. Beyond that, what?

A walk around the old town and up to Bratislava castle.

Get an hours bus tour round the city.

Hire a bike and head out to Devin Castle then along the Danube to Austrian border and back.

In the city i enjoyed the transport museum.

If you like beer try Dunajský Pivovar – this is a brewery that is on a boat on the danube.

A walk around the old town and up to Bratislava castle.

That.

Take the tram/trolleybus around Petrzalka and marvel at the (rubbishness of the) Soviet era architecture.

Can you still go up the bridge?

Just looking on google maps, a lot has changed since I was last there!

I’m staying at Devin castle, so the walk is there.
Old town and bridges look good.

As said, a trip up to the castle on the sight seeing bus is ok. The old town is not so big so you’ll see most of it in an hour or so walking around. It’s typically eastern block in the fact that there’s graffiti everywhere and could do with a spruce up.
If you go for a beer just be aware that a normal beer is 12 per cent alcohol there.

iolo – the typical beers are not 12% alcohol although this is an easy mistake to make. Beers are labelled in plato units. 10º is typically 4% alcohol and 12º is typically 5% alcohol.

matt outandabout – old town is nice for a couple of beers and to enjoy the views (the women are stunning :D).