Hi I am in need of advise for transfers and transport while in Paris. We will be travelling via Eurostar from London and arrive at Paris Gare du Nord train station at 7.50pm on 14th April.

I need advise on transfers from Gare du Nord to a hotel in Cergy Pontoise, 95030
France. I was thinking of using the RER lines but don't know which one. We will be travelling as a family of five so will be great to compare cost of journey with getting a taxi.

For our local city tour we would like to see the Effel tower and some other central Paris attractions on the 15th April and would be great to know which RER line to use from Cergy Pontoise, 95030 and the train stop for our destination.

I also need information on how we can get from Cergy Pontoise, 95030 to Soisson train station on the 16th

Thanks for your assistance.