We (parents & 12 year old daughter from Australia) will spend 5 weeks travelling from Mex City to Cancun in December / January & are currently fine tuning our itinerary. A preferred option has us in Merida from Tuesday to Friday. A less preferred option has us in Merida Friday to Monday.

In both cases we will be heading from Merida to Santa Elena to explore Uxmal, cenotes etc. by car, so our time in Merida will be pretty-much city-bound

I'm aware that there are lots of activities / festivities in the city over the weekend, so I'm trying to gauge whether this adds enough to the experience to go with the less preferred itinerary.

What do you think? How 'unmissable' is Merida on the weekend compared to during the week?

Tough call, IMO! I think it depends on what experiences you are most interested in including in your time in Merida.

I certainly enjoyed the lively festivities and dance performances and strolling the markets over the weekend. But, if I recall -- and I could easily be wrong -- at least some of the places I wanted to visit closed either mid-day or all day on Sunday. And one of my priorities was the very good Museo Regional de Antropología, which is -- I believe -- closed on Mondays. So you might want to check on the opening hours of any places you particularly want to see so you can figure out which block of time better suits your interests.

Too, I'm not sure how Uxmal or the other sites of the Ruta Puuc -- or the Loltun Cave (if that is of interest) -- are affected by weekends. If no one who responds to your post speaks to that, consider contacting either the Flycatcher Inn or Pickled Onion to ask. Both are well-reviewed lodgings along the Ruta Puuc, so you might want to decide which one you would most like to reserve and then ask them this question. Just a thought!

I don't think you have a bad choice -- just a tricky one!

Personally, I always make sure I am in Merida on the weekend. But if you go with your preferred option, you can still go to Santa Lucia park (a few blocks from the zocalo) for the free music and dance performances that occur every Thursday night. Don't miss that.

We spent almost a week in Merida, including the weekend - the weekend was fun, to be sure, but there is live music other nights of the week as well. We went to Santa Lucia park on Thursday and there was a market near there also. And it is a good point about some things being closed on Sundays, which could impact your sightseeing.

In the main square on Sunday, we enjoyed the market booths, the extra food carts that were around, and the people-watching. It was very festive. I'm not really into shopping, so the market itself kept my attention for about an hour. For shoppers, it is probably more interesting. The "entertainment" in the square that Sunday was an annoying clown with a horribly grating voice - projected very loudly all over the square. There was no escape. So we didn't stick around long. It would have been a lot better to have had a band playing and we probably would have stayed longer.

What dates are you looking at? I ask because many activities and restaurants close here during Xmas week.
Santa Lucia aside, all our other less touristy parks have music once a week, as well.

There are also 2 zoos, many museums, nearby ruins and cenotes and countless other forms of entertainment to be had during the week. Merida's a large city with both colonial and modern things to do.

Thanks for the replies - I'll take it all on board.

FYI, my itinerary options are:

1) Mex City, bus to Oaxaca, overnight bus to San Cristobal, bus to Palenque, bus to Campeche, bus to Merida (for weekend), hire car for Santa Elena, Puerto Morelos.

2) Mex City, bus to Oaxaca, internal flights to Palenque, bus to Campeche, bus to Merida (no weekend), hire car for Santa Elena, Bacalar, Mahahual & Puerto Morelos.

1st option is the basic Gringo Trail by bus, including Chiapas highlands & Merida on the weekend with a minor road trip at the end. No time for Bacalar / Mahahual though.

2nd option avoids a couple of grueling bus rides (a key concern travelling with a child, hence preferred option) and includes Bacalar / Mahahual. But we miss out on Chiapas highlands & Merida on a weekend.

Actually, there is a third option involving a longer road trip, but I'm cautious about the amount of driving.

3) Mex City, bus to Oaxaca, internal flights to Merida (for weekend), hire car for Santa Elena, Palenque, Calakmul, Bacalar, Mahahual & Puerto Morelos.

Thoughts on these options very welcome....

FWIW: I haven't been to Mexico City, Oaxaca, Bacalar, or Mahahual yet, but I have been to all the other places you mention, and FWIW, I adored San Cristobal del las Casas. I considered it a highlight of my time in the area.

I wonder -- if you take that 1st option, would you have time for a night or two in Tulum? That might give you a chance for the beach time that you would be giving up by skipping Bacalar and Mahahual....

Should be a great trip whichever route you choose!