That sounds a bit harsh, but I mean it kindly.
Although Marazion has little in the way of historical buildings it nevertheless has the usual range of attractive architecture and narrow lanes which one might expect in a fishing-village-turned-visitor-attraction (and artist hotspot). So a wander is well worthwhile, not least for the creations on display in the art /craft shops.
You will find the odd interesting building too: the occasional small, granite 'fisherman's cottage', the typically-Victorian ostentatious town hall and a house in which Charles ll is reputed to have stayed the night before his escape to the Scilly Isles (after the Battle of Naseby and before he was crowned).
So yes, a wander round Marazion is worthwhile.
On a tiny island in beautiful Mount's Bay sits Saint Michael's Mount, the dramatic castle looming over the landbridge that can be crossed on foot only at low tide. The varied and exciting history of the island includes ancient sun-worshipping religious cults, Phoenician traders, an appearance by the archangel Michael, an evil giant named Cormoran and a giant-killer named Jack, and an invasion attempt by the Spanish in the 1500's. The castle has been the home of the St. Aubyn family for the last 300 years.
Crossing to the island on foot is free - taking the ferry is cheap, too. Walking around the island is free, but going into the castle grounds or into the castle itself costs money. It is a National Trust property and worth the reasonable entry fee. Pick a pleasant day and spend at least 3 hours here. Follow the link below for more information, including admission fees, opening dates, tides, and times.
Once you are in Marazion you have to visit the most interesting attraction from those places which certainly is Saint Michael's Mount. A wonderful island containing a great castle perfect placed on a mountain. Until 12:30 PM you can even follow the path to the castle by walking while when return you will have to make the trip by boat as the sea is coming back covering the cobble road. Is quite impressive.
See Marazion travelogue for details.
St Michael's Mount is hard to miss and dominates Mount's Bay. There is a small harbour on the island , a tourist/ ticket information/ souvenir shop, cafe and a few cottages.
Around the castle are exotic gardens; did you ever expect to see palmtrees and cacti in England? Well now is your chance.
After a short steep climb you reach the castle.
open to public:April to October and most other weekends
Mon-Fri ; 10;30 17 ;30