• For a comprehensive list of commemorative plaques for your country, go to openplaques.org
• English Heritage (english-heritage.org.uk) have helpfully created a GPS-enabled Blue Plaques App for your smartphone. Not only does it provide some guided routes, but it allows you to quickly identify any Blue Plaques close by.
• Paul Talling, London’s Lost Rivers, Random House Books, 2011.
• Tockner, Klement, Uehlinger, U., and Robinson, Christopher T., Rivers of Europe, Academic Press, 2009.
• Most cities have a travel website that allows you to plan your journeys, but an excellent universal tool is rome2rio.com
• Paris transport: www.ratp.fr/en/
• London transport: tfl.gov.uk/plan-a-journey/
• Although this doesn’t strictly follow the rules of this challenge, if you’ve a spare 24hrs, you might want to take on the Tube Challenge (thetubechallenge.com), and attempt to visit every London Underground station (all 270) in the shortest amount of time possible. The current Guinness World Record stands at 15 hours 45 minutes and 38 seconds. A similar challenge exists in New York City – rapidtransitchallenge.com
• funimag.com – a web magazine about funiculars. Includes a database of all the funiculars in Switzerland.
• Search for ‘list of funicular railways’.
• The best way to plot a route crossing the bridges in your city is to use an online mapping tool, such as Strava, Ride with GPS or MapMyRun.
• A simple starting point for finding vertical kilometres is to search for any mountains higher than 1000m above sea level, which if you’re near the sea would also tick off a Sea to Summit challenge.
• If you don’t have any summits higher than 1000m, then you’ll need to create a route incorporating enough hills to bring you up to 1000m. But the idea is to do it in as short amount of time as possible.
• Grouse Grind challenge: https://www.grousemountain.com/grousegrind/faq
• Humphreys, Alastair, MicroAdventures, William Collins, 2014.
• Search online for ‘bicycle sharing schemes’.
• The European Cyclists Federation provides some history behind bike sharing schemes in Europe: https://ecf.com/
• To learn more about all things Monopoly, go to http://monopoly.wikia.com
• Search online for ‘List of licensed and localized editions of Monopoly’ to see if your country or town has its own board.
• The ÖTILLÖ is the original SwimRun race and the one that inspired Tobias and his wife Zayne, when they completed it in 2014. There are a number of SwimRun races around Europe that you can set your sights. otilloswimrun.com
• For a list of international SwimRun events that might provide inspiration for planning your own SwimRun, visit swimrunfrance.fr
• everesting.io – an online calculator that helps to work out how many repetitions of a segment you need to do to reach the height of Everest.
• everesting.cc – the home of all things Everesting and where you'll find the Hall of Fame and what climbs have already been Everested.
• https://www.grousemountain.com/grousegrind/faq – for information about the Grouse Grind.
• Feles du Grand Colombier – http://www.felesducolombier.fr
• Club des Cingles de Mont Ventoux: www.clubcinglesventoux.org/en/
• Les Barons du Soulour: http://baronsdusoulor.monsite-orange.fr
• Il Brevetto del Grappa in Italy (10 ascents by road and an eleventh on an MTB): altopianobike.com/notizie/ultime-notizie/il-brevetto-del-grappa.html
• timeanddate.com/sun – gives the exact time for sunrise and sunset wherever you are in the world.
• A 954km route through Germany passing 100 castles: http://www.nrw-tourism.com/a-100-schloesser-route
• Search online for ‘lists of castles’.
• peakbagger.com – provides tons of lists, worldwide, for aspiring peak baggers.
• peaklist.org – lists over 10,000 mountains worldwide.
• thecolcollective.com – an inspiring resource of videos and information about how to tackle some of the greatest climbs in the world.
• centcols.org – Home of the Club des Cents Cols.
• www.aukweb.net/ocd/ – UK site for the Ordre des Cols Durs.
• https://uctistes.wordpress.com/about/ordre-des-cols-durs/ – Union des CycloTouristes Toulousains – the home of the French club.
• www.rhinecycleroute.eu – provides information on the Rhine Cycle Route, AKA EuroVelo 15.
• http://www.danube.travel/ – information about the Danube that will help you plan your trip.
• http://bicyclegermany.com/elbe.html – information about the Elbe River Cycle Route.
• naturalarches.org – a great source of information for finding natural arches around the world.
• Search for ‘twin towns’ or ‘sister cities’ for lists of twinned towns.
• twinning.org – provides information on history of twinning.
• Wikipedia is a great source of information for finding out if your town is twinned with another.
• Use websites like RidewithGPS or Strava to create a route between the two towns. Create a start point and a finish point, and let the mapping tool plan the rest.
• bikepacking.com – a brilliant resource and source of inspiration for planning your bikepacking adventure.
• bikepacker.net – another great website packed with interviews, reviews and reports from the bikepacking scene.
• List of French refuges: www.gites-refuges.com (in French).
• The Club Alpino Italiano provides a list of all their refuges by area www.cai.it (in English, French and Italian).
• Mountain Bothies Association – www.mountainbothies.org.uk
• http://www.perimeterbicycling.com – The Perimeter Bicycling Association of America.
• HardasTrails.com – Tobias’s blog and where a lot of the information in the book can be found.
• Ordnance Survey in the UK: https://www.ordnancesurvey.co.uk/osmaps/ – an excellent online mapping tool that will help you to plan your adventures in the UK.
• Strava (strava.com) has an excellent ‘route planner’ that will select a route based on popularity – saving you a lot of time in the process.
• viewranger.com has an app that allows you to download local maps to your phone from over 20 countries. For some countries, such as the UK and France, they offer a modest annual digital subscription service that allows you access to your respective country’s maps.
Benson, Jen and Sim, Wild Running:150 Great Adventures on the Trails and Fells of Britain, Wild Things Publishing, 2014.
Brotheron, Lyle, The Ultimate Navigation Manual, Collins, 2011.
Clayton, Roy & Turnbull, Ronald, The Welsh Three Thousand Foot Challenges: A guide for walkers and hill runners, 2nd Edition, Grey Stone Books, 2010.
Gatty, Harold, Finding Your Way Without Map or Compass, Dover Publications, 2003.
Gooley, Tristan, The Natural Explorer, Understanding your landscape, Sceptre, 2013.
Gooley, Tristan, The Walker’s Guide to Outdoor Clues and Signs, Sceptre, 2015.
Humphreys, Alastair, Grand Adventures, William Collins, 2016.
Thomas, Clive, GPS for Walkers: An introduction to GPS, digital maps and geocaching, Pathfinder Guides, 6th Edition, 2013.
Turnbull, Ronald, Lakeland Mountain Challenges: A Guide for Walkers and Fellrunners, Grey Stone Books; 2nd edition, 2010.
Turnbull, Ronald, The Book of the Bivvy, Cicerone Press, 2003.
Turnbull, Ronald, Three Peaks, Ten Tors: And Other Challenging Walks in the UK, Cicerone Press, 2007.
Smith, Phoebe, The Book of the Bothy, Cicerone Press, 2015.
Warren, Simon, 100 Greatest Cycling Climbs: A Road Cyclist’s Guide to Britain’s Hills, Frances Lincoln, 2010.