We visited Zarcero completely by accident on our 2001 trip to Costa Rica but we stopped when we saw the topiaries in the central park. This time we visited intentionally on our way back to Alajuela from the Arenal region. The cathedral has been painted gray but otherwise it looks much the same.
There's nothing specific to do here but it's a nice place to wander around the crazy topiaries.
The town around the square is pretty lively now as well. It was a quiet place on our last visit. Now there are a lot more restaurant choices nearby.
There aren't really any signs or indications as to why all of this is here or what exactly is going on so it's just left up to your imagination.
Not far past Zarcero and still on the way to San Jose is Sarchi. This cathedral is the center of town. Sarchi is best known as a crafts destination within Costa Rica. There are several co-op stores on the roads into town. Woodwork is the most common item.
This is an oxcart. You may think it to be a very large oxcart and you'd be right. In fact, this is the world's largest oxcart. It had to be somewhere so it might as well be in Sarchi.
Here's another view of the world's largest oxcart just in case you're not willing to stop and see it for yourself.