The train
Avanti West Coast runs the fast service from London Euston to Manchester Piccadilly, typically about two hours and five minutes to two hours and fifteen. Some trains are slower. Piccadilly is the station you want for a city break. A minority of fares and older patterns still involve Manchester Victoria or a change; Victoria is useful for the north of the centre and for some Liverpool connections, and a nuisance if your hotel is at Piccadilly or in the Northern Quarter and you did not mean to arrive there.
Euston and Piccadilly
Euston is a Northern line and Victoria line station on the north side of central London, a short walk from King's Cross if you are joining the trip from the east coast. A Euston or King's Cross hotel is the logical London night before this train. Piccadilly is on the south-east edge of Manchester's centre, with the tram (Metrolink) outside and a walk into the Northern Quarter, Chinatown and Piccadilly Gardens. Spinningfields and Castlefield are a longer walk or one tram hop. Deansgate and the Beetham Tower sit over that walk.
Flying and driving
You can fly into Manchester Airport from London. For a city break it is rarely the better door-to-door journey: the train lands you in the centre, the plane lands you at an airport that then needs the train anyway. MAN is the right airport when you are arriving from abroad or from a UK city with a thin rail link, not when you are standing at Euston.
Driving is the M1 or the M6, about three and a half to four and a half hours depending on the day you choose to meet Birmingham's traffic. A car is optional in the centre and useful if the Peak District is the second half of the weekend. Liverpool is the short onward hop — see Manchester to Liverpool.
What to do with the two nights
The Northern Quarter, a museum morning, and whichever of the football grounds you actually have a ticket for. Canal walks toward Castlefield fill a sunny afternoon. You do not need a list. You need a hotel on the right side of the tram so the late train back to the hotel is one stop, not a taxi argument.
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