What would be the best, "cheapest" way to get from London to Amsterdam? Would it be cheaper to go from Paris to London? We want to add London on to our RS trip either at the beginning or end.
You could go by train via Bruxelles (4h40 total), fares start from € 49.
Megabus.co.uk do coaches from London to amsterdam and London to Paris really cheaply if you book early you can get them for less than £15 return or £10 for a single
To make the trip in 4h40min requires taking the Eurostar from London to Brussels and a Thalys train from there to Amsterdam. The best combined discount fare is €71.50 (€42.50 for Paris-Brussels booked on eurostar.com plus €29.00 for Brussels-Amsterdam booked on thalys.com). The cheapest route by train is the Eurostar to Brussels and an IC train from there to Amsterdam. The trip will take an hour longer, but the cheapest fare is €61.50 (not €49.00). Book the entire route on the NS Hispeed site. Your Brussels-Amsterdam ticket will be good on any IC train so you could spend a few hours in Brussels and then jump on any IC train. Booked well in advance, flights on easyJet from London Gatwick, London Luton, London Stansted, or London Southend are cheaper than taking the train. Fares on British Airways from Gatwick are competitive. You can travel overnight on the Dutch Flyer (train-ferry-train) for £63.00 and save the cost of a night in a hotel. Or travel during the day for £39.00.