Take the National Express coach or train from Heathrow to London Euston then direct train to Blackpool North (total travel approx. 3.5–4.5h). Prebook tickets for best fares.
Walk the seafront to see the Blackpool Illuminations (running annually into early November — usually dusk–11:00pm); great first-night welcome to the town.
Famous amusement park with rollercoasters, shows and indoor Winter Gardens options; opening hours vary seasonally (usually 10:30am–5:00pm late season).
Indoor option: Sandcastle Waterpark for relaxed fun or visit the Winter Gardens for a theatre tour — check opening times (usually 10:00am–6:00pm for attractions).
Take direct or connecting train to London Euston then transfer to Heathrow (allow 4–5 hours total including connections). Prebook seats/baggage if possible.