How to take the RER from the Gare De Lyon to the Gare Du Nord

If you want to opt to make the transfer between the Gare De Lyon and the Gare Du Nord by public transport, taking the RER train is the best option.

The four positives are:
(1) It’s comparatively fast - it’s a two station hop on Ligne D (Sud) - the green line, so you can be the concourse at Gare Du Nord, within 25 mins of entering the RER station at the Gare De Lyon.
(2)The line D platforms at the Gare Du Nord and Gare De Lyon stations have both been brightened up; and numerous staff can usually be found on the platforms at Gare Du Nord, so the station has lost much of what had been a somewhat intimidating atmosphere.
(3) It's cheap, a single central zone metro ticket can also be used on the RER.
(4) It's generally reliable, you won’t have to wait more than 12 minutes for a train and delays are very rare.

Not so great:

• The air-conditioning on the RER trains can be temperamental, so on a hot day, particularly if you are managing heavy luggage, it can be a tad uncomfortable
• Also the end-to-end the journey can be more confusing than you might imagine, hence the info below.

’You will need to access RER Line D by passing through the Hall 3 at Gare De Lyon.
It is at at lower level to where the TGV and Lyria trains arrive, but how you access Hall 3 will depend on which part of the station your train has arrived at.

The RER station is at one end of the Hall 3 concourse.
(This view above of Hall 3 was taken from the entrance to the RER station, looking in the OPPOSITE direction towards Hall 2).

The only exit is to walk ahead towards the front of the train.
You will then be on the Hall 2 concourse, the access, pictured above, down into Hall 3 will be in the middle of the concourse.

Be prepared to have to navigate through the crowds of people waiting for trains.
The entrance to the RER will then be at the far end of Hall 3.

Don’t walk ahead to the far end of the voie/platform at the front of the train.
Instead use the stairs and escalators you will see along the voie/platform, they will have the RER symbol on the signs above them and they lead down into Hall 3.
One of the sets of stairs leading down to Hall 3 can be seen in this view above; there also escalators available.

If you’re travelling in the front 3 – 4 coaches of the train, these stairs/escalators to the RER, leading down to Hall 3, will be behind you when you step off the train
Don’t be tempted to head to the Hall 1 concourse, which you will see ahead of you, the easiest access to the RER will be via Hall 3.

When you’re in Hall 3 you will have to turn to the left or right depending which set of stairs and escalators you will have used.
What you need to do is head in the opposite direction to the atrium which connects this Hall 3 to Hall 2.

When you reach the end of Hall 3, there are escalators and elevators which lead down into the RER station - the image above left is taken from the foot of this escalator, looking in the opposite direction up to Hall 3.

Your end-2-end train journey ticket will not include the RER, so you will need to buy the Metro-Train-RER ticket, which costs €2.50.

Worth knowing is that Paris has pretty much transitioned to a Pay As You Go system for its public transport network, based on navigo cards.
There are two core methods of using navigo:
1 - A plastic card which is automatically issued by ticket machines and ticket counters when you inform the machines or staff, that you don't already have a card - the cost of the card is €2.
2. Downloading the navigo app to a mobile device.

The big plus of bothering to download the mobile app, is that you can then use mobile banking to pay for tickets to be added to it, so can then avoid the ticket machines and counters!

The staffed ticket counter in the RER station is only open at certain times of the day, so to mitigate against this, multi-lingual staff can be assigned to each ticket machine, to ensure the correct ticket is purchased.
However, queues of more than 10 people per ticket machine can be typical

The excellent parisbytrain website has all the info you will need about metro tickets.

You need to take a Ligne D (Nord) train.
When you have descended to the platform remain in the area at the foot of the escalators/stairs.

It will be the most crowded part of the platform/voie, but you will then be able to board towards the rear of the train when it arrives; and this is the best option, as explained below.
ALL Line D trains heading north will be calling at Gare De Lyon - though check the departure indicator, as the next train can be departing from voie 1 or voie 2.

The train will be double deck, but don’t bother with finding a seat.
It’s easier to wait by the doors as the travel time is only around 7–8 mins, though allow room for people to alight and board at the intermediate station, Châtelet – Les Halles.

On arrival at Gare Du Nord there are multiple sets of escalators and lifts / elevators leading to the level above - you will find yourself in a mall.
Those located nearest to the rear of the train will have the quickest and least confusing access to the main line departure concourse.

Follow the signs pointing to the 'Grande Lignes' trains.

You will exit from a passage way, which resembles a shopping mall, into an atrium from where you will see the main concourse at the Gare Du Nord above you.
If you have used the escalator which will be on the platform, which you will find towards the rear of the train, then when you have ascended you will see this atrium ahead of you.

In this view above right, the exit from the RER station is over to the left and the escalator in the middle of the picture is the main link up to the main departure concourse.

Take the escalators or lifts up to the main concourse in Hall 1, where the trains will be lined up at their respective voies/platforms over to the right.

When you have ascended up to the main concourse, you will have to go up another level to access Eurostar departures in Hall 2– the ‘Hall du Londres’.

Eurostar is currently recommending Standard and Plus ticket holders should be at the Eurostar departure area 75 - 90 mins before departure; and that Business Premier ticket holders should be there 45-60 mins prior to departure.
The departure gates will close 30 mins prior to departure for Standard and Plus ticket holders; and 15 mins prior to departure for Business Premier ticket holders.

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