St Andrews is three towns sharing a street: a medieval ecclesiastical capital, a university, and the home of golf. You do not need to play golf to justify the journey. The cathedral ruins running down to the sea, and the castle on its rock, are the older story and they are free to look at from the scores — the lanes that drop to the shore.
It is small. A night is generous. A day from Edinburgh is possible and a little rushed if you also want a walk.
See
The cathedral
Ruin, tower, and a churchyard on the cliff. Climb St Rule’s Tower if it is open and your knees agree.
The castle
A short walk along the coast from the cathedral. The mine and counter-mine are the odd, memorable bit.
The West Sands
A long beach. Wind is part of the design. Walk as far as the light is good.
The Old Course, from the path
You can see it without a tee time. Do not wander the greens. The clubhouse is not a public lounge.