A restored tin/copper mine near the Geevor mine, but Levant has a working beam engine lovingly restored by volunteers which can be seen working on three days each week.
In one day you can visit one or both mines and the nearby Pendeen lighthouse. Very rewarding.
By the way, others have mentioned the Minack Theatre and Porthcurno beach. From the Minack you can climb down the cliff to Porthcurno - another combination you can do in a day.
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