Why do some posters keep banging on about multiple other places for the OP to visit?! She asked about Blackpool. She wants to go to Blackpool! Can people not be arsed to listen or something?
Or do they think that their (alternative) opinion - that the place they are suggesting will be 'better' - is so important and superior?! 🙄
Just get a cheap Travelodge room @MochiPie No way will it be enjoyable doing it in one day. Ignore the people bashing Blackpool. Most people bashing it have never been. Yes it's not glamourous, and you need to avoid the backstreets a bit (especially after 7pm) but there is loads to do there, a big beach, 3 piers, the tower, the waxworks, the sea life centre, the funfair and pleasure beach, loads of arcades, pubs, and restaurants, and 100s of shops. AND the illuminations if you go after 29th August.
Book it, you'll enjoy it. Ignore the haters and naysayers.
BUT I wouldn't try and do it in one day. It will be so exhausting! Book a cheap room, and you can enjoy it properly, enjoy the day, and go out on the night, and see the illuminations, go to a pub or a restaurant, and go back to the hotel late, knowing you haven't got to drive home, or get a train home. If you try and do it in one day, you will have to get the train back at 7.30pm! (Gets into London at half ten.) There's one an hour later but it doesn't get into London til half past one in the morning!
Book it tomorrow! have fun. 
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