Can I visit the Blue Mountains from Sydney without a car?

With just one day, I would focus on the Katoomba area and one or two lookouts rather than hop between several towns. The train gets you to the mountains, but the sights are not on the station platform; include the local bus or walking leg in your plan. If you want a long hike, sunset or a slow dinner, stay overnight. Trying to fit all three into a same-day return would be rushed.

Take a warm layer and decide on walks only after checking the weather and current track notices. The mountains can feel very different from central Sydney on the same day. Leura or Katoomba makes a sensible lunch stop, but a popular cafe can take time on a weekend, so keep a backup in mind. Leave enough daylight for the walk and enough margin to reach your return train.

Yes. Trains from Central reach Leura and Katoomba on the Blue Mountains line, and a day trip is possible if you start early. Pick one village and a small number of lookouts or walks instead of trying to cover the whole region. Leura is an easy place to pause for a cafe lunch; Katoomba is a practical base for nearby sights and local transport. Check the current train timetable, local bus connections, track notices and weather before setting off.

If you want longer walks, an unhurried meal or several villages, stay overnight. A tour or car can simplify widely spaced stops, but it is not required for a focused first visit by train. Leave enough daylight and a clear return plan, particularly in winter.