HELP! All the trains are sold out!

That can happen if you're trying to book your travel last minute. If the tickets are sold out they are sold out, trying to buy a ticket at the station won't change that.

But what you can do is to take a bit of a detour and break up the journey. E.g. take the train to Kalmar in the morning. Spend a few hours there and have lunch, and then continue by train to Stockholm.

Unfortunately, we tried a number of other options: via Gothenburg, Malmo, and now Klamath, but none have viable options on to Stockholm. But we appreciate the suggestion. We were really surprised that the trains would be all sold out!

Unfortunately, we tried a number of other options: via Gothenburg,
Malmo, and now Klamath, but none have viable options on to Stockholm.

Is that a creative way to spell Kalmar? I see a couple of departures with free seats from Kalmar to Stockholm on Sunday. Where are you looking for tickets?

We were really surprised that the trains would be all sold out!

I'm not. Stockholm-Copenhagen is a popular route and Sundays are a popular travel day. Especially this time of the year, there are probably a lot of people travelling home from their vacation this summer.

Sorry, Kalmar autocorrected to Klamath. Our problem is that we’re coming from Aero in the morning on the 8:30 ferry and need to return a rental car so we won’t me able to leave Copenhagen until about 12:30 or 1:00 pm. The 1:00 train gets into Kalmar at 4:59, but the only train I see from Kalmar leaves before that. I appreciate your help, though.

I can see two daytime options on Flix Bus- bus to Gothenburg then Flix Train, also an overnight option.

I don't think either of the two daytime options is "terrible" unless you mean the cost.

I can also see 3 day options on VyBus, also changing at Gothenburg, this time bus all the way- https://www.vybuss.com/#!/

You may not like the amount of time the bus options take, but you don't seem to have too much choice.

There is a 1327 train CPH-Gothenburg arriving 1740, then an 1824 arriving STH 2131;
also a 1427 arrive Goth 1840 or 1527 arrive 1940 then Gothenburg depart 2024 STH arrive 2330

Then you have a problem.

There is a 16:36 departure from Kalmar to Stockholm, but it won't give you much time in Kalmar. Another option is to use regional trains to Stockholm, although it involves a couple of changes.

Or take the train via Gothenburg.

You could get a new rental car and drive to Stockholm on a one way rental. If you take the local train from CPH into Sweden (Malmo), there are cars available from Sixt located at the train station. Appears to be much cheaper than renting the car from CPH airport probably due to it being the same country. Return it to ARN airport (open late) and take the airport train back to Stockholm.

Flying is honestly not that bad for last minute, I see some later evening flights for around $300 each depending on what bags you have.

Swedish House Mafia plays in Sweden once this year (it's also the first concert in Sweden since 2019), in Malmö on Friday but the festival is 2 days so some concert goers stay to Sunday. Trains are sold out on Saturday too which is much more uncommon.

The train to Gothenburg will probably not be comfortable experience since they sell an unlimited number of tickets and some festival vistiors will go that route too but still an option. There is also a bus replacement between Mölndal and Gothenburg so it will be three legs in total to Stockholm with train+bus+train. Use the filter-button on the SJ site or app to add Göteborg C in the "travel via" box to get it all on one ticket.

If you're in Denmark or Sweden, I suggest going to a train station and see if someone in customer service can help you figure out something. On a recent trip to Europe I ran into a similar situation where all the trains from Stockholm to Gothenburg were fully booked. Someone in customer service at the Stockholm train station was able to figure out an alternative route that took a different route requiring two trains.

Thank you all! We did go to the train station today and they were able to find trains that work for us. We just couldn’t get them online.

We did go to the train station today and they were able to find trains
that work for us.

What option did they find that you couldn't find online?