City Thameslink station to Gatwick
 

The flat we have rented appears to be closer to City Thameslink station that Black Friars. I am not familiar with this station. Is it as well to start my trip to Gatwick from here?
Is there a great difference in comfort between coach and first class, given that it's a 45 minute trip? I would consider it if the luggage area had more room

There is massive construction work on the line between gatwick and Blackfriars so the direct trains are few and far between if at all depending on the time you arrive and depart. You may have to go via Victoria station and change to the district or circle line.

I am not in London but above advice seems incorrect. There are two Thameslink lines from the City to Gatwick and although the main line via London Bridge station is under construction there is a secondary line past the Crystal Palace park that continues to Gatwick. Allow an extra 15 minutes. Going via Victoria does not sound prudent: double the time and more expensive.

City Thameslink and Blackfriars stations are just yards apart. Blackfriars offers the most sensational arrival to London and City Thameslink is like a tube stop.

As with most train routes in and around London, there's no single straight answer to the poster's question. The scale of new building and reconstruction on London's trains and tubes means a constantly-changing amount of disruption.

Most of the time, there are direct weekday trains from City Thameslink to Gatwick every 15 minutes, currently taking about 50 mins. As tom mm says, it's never a good idea right now to change between tube and train at Victoria if you don't have to, and doing so on most weekdays will inevitably take longer than going straight from the City

Services from City Thameslink will be particularly liable to be suspended at weekends until early 2018 (the current 50 min journey time includes the delays from the ordinary disruption jamikins has pointed out), and you need to check options for the time and day you propose travelling at www.nationalrail.co.uk.

If you're travelling during a weekend the whole City-south coast Thameslink line is suspended, getting a taxi to Victoria for Gatwick might be an easier option than unnecessary luggage-encumbered dealing with the tube/train connection there.

DO NOT be tempted, except before 0800 on Sunday mornings, to get a car or taxi to Gatwick.

And to answer your other point, I have no idea why they offer a first class on these trains. I haven't noticed any great difference in seat configuration or luggage space, or any additional services that would make it any more comfortable for this sort of journey.

If you're thinking of booking in advance, you don't need to do that now, either: wait until you're here and can check what the position is about engineering works and the like.

1st class on Gatwick trains from Farringdon area to Gatwick is that there is a paltry of first class seats that look just like the others and IME may even be occupied by folks not holding first class tickets until the conductor shows up - yet in theory there is extra space for bags because first class is generally or should be rather empty. I guess for the small extra fee it may be worth it with a lot of luggage.

Thank you. It's all very useful. Construction shouldn't be too big a problem as we are travelling on a Friday Morning, having an 11:15 flight from Gatwick. Sounds simpler to go to Blackfriar's.
We don't have a lot of luggage, but if trains are crowded, we wouldn't be the fastest onboard for battling for luggage space.

Southbound trains at Blackfriars board practically on the south bank of the Thames so if you think City Thameslink is closer then it surely is. Always buy rail fares for multiple people together as there is sometimes a group discount. Congratulations on choosing an interesting, central, less touristy area to stay in.

Congratulations on choosing an interesting, central, less touristy area to stay in.>

Yes but kind of dead at night as the area is I believe mainly offices and lacks any neighborhood feeling - at least around Blackfriars

In that area you should check out the lovely Art Nouveau pub The Blackfriar the interior is very well worth seeing.

Well yes there are pubs everywhere - for the average business crowd - always amazingly out drinking it seems but you probably won't find many things open at night besides pubs.