What is a Mile Builder

What is a Mile Builder

A Mile Builder is a sailing trip designed to help sailors log more miles and gain offshore experience. These trips are often used by those working toward sailing qualifications  like RYA certifications or simply to improve navigation, watch-keeping, and seamanship skills in open water.



Why is crossing the North Sea from the Netherlands a good idea?


Sailing across the North Sea from the Netherlands is a popular mile-building route because:


  1. Challenging Yet Manageable – The North Sea presents tidal streams, busy shipping lanes, and changing weather, making it a great training ground without being excessively dangerous.
  2. Varied Conditions – Sailors experience different sea states, winds, and weather patterns, improving adaptability.
  3. Navigation Practice – The trip requires good passage planning, including night sailing, shipping lane crossings, and sometimes fog.
  4. International Sailing – It allows sailors to experience customs procedures, different maritime rules, and offshore passage management.
  5. Good Destinations – The crossing typically leads to the UK (e.g., Ipswich, Lowestoft, or Harwich), or even Norway, offering interesting ports and cultural experiences.





Sailing from Medemblik in the Netherlands to Harwich in the UK is a fantastic offshore passage across the North Sea, covering around 150-170 nautical miles depending on your route. It’s a proper Mile Builder journey that combines coastal navigation, offshore sailing, and international passage planning.


✅ How to Plan the Journey from Medemblik to Harwich


1. Route Overview


Your journey will roughly follow this route: Medemblik → Den Helder → North Sea → Harwich (or Shotley Marina, just up the river)

Key Legs of the Passage:


  • Medemblik → Den Helder (40NM, coastal sailing through the IJsselmeer and Wadden Sea if via Kornwerderzand)
  • Den Helder → North Sea Crossing (110-130NM depending on route)
  • North Sea → Harwich via the Sunk Traffic Separation Scheme (TSS) and Felixstowe Channel


2. Route Options


You have two options to get out into the North Sea:

Route

Pros

Cons

Via Kornwerderzand & Den Helder

Shorter

Lock passage + shallow tidal waters

Via IJmuiden

Longer, but deeper water

Extra 40NM



3. Tidal Planning


Crossing the North Sea is all about the tide – both in the Netherlands and around the UK East Coast.

Important Tidal Factors:

  • Den Helder to TSS: Timing your departure from Den Helder to ride the ebb tide into the North Sea.
  • North Sea Crossing: Tidal streams run southwest to northeast with strong currents – you'll need to calculate course to steer.
  • Harwich Approach: Plan to enter Harwich (River Orwell or River Stour) on the flood tide.



4. Shipping Lanes (TSS)


You must cross the TSS (Traffic Separation Scheme) at right angles:

  • The Sunk TSS is one of the busiest shipping areas in Europe.
  • Plot your waypoints and keep your VHF radio on Channel 16 + 74 to monitor traffic.



5. Weather Windows


The North Sea can be rough, even in summer. The best months are:

  • April – September for lighter winds
  • But always check a 5-day forecast before crossing.

Good weather apps:

  • Windy
  • MeteoGroup
  • Windfinder
  • PassageWeather



6. Night Sailing


Expect at least one night at sea on this journey, especially if you're doing 4-hour watches.
A few night sailing tips:

  • Use red lights for night vision
  • Plot hourly log entries
  • Stay clipped on


7. Arrival in Harwich


Popular Marinas:

  • Shotley Marina (quiet, scenic spot upriver)
  • Levington Marina
  • Pin Mill, (also a quiet and pretty spot upriver) via the River Orwell
  • Halfpenny Pier (right in Harwich town)

You'll need to call Border Force on Channel 11 or phone them on arrival for customs clearance.




Typical Passage Plan Summary


Leg

Distance

Duration

Notes

Medemblik to Den Helder

40NM

6-8 hrs

Coastal leg, locks at Kornwerderzand

Den Helder to Harwich

110-130NM

24-30 hrs

Offshore crossing with TSS

Total Passage

~150-170NM

30-40 hrs

Overnight + international



Why This Journey is Perfect for Mile Building:


✅ International passage
✅ Night sailing
✅ Offshore navigation
✅ TSS crossings
✅ Tidal planning




Gear Checklist:


Essential Gear

Nice to Have

Lifejacket + PLB

AIS Transponder

Paper Charts + Almanac

Radar Reflector

VHF Radio

Satellite Tracker

Flares

Autopilot


Final Thoughts


Sailing from Medemblik to Harwich is a proper adventure — not just about logging miles, but about learning to handle tides, traffic, and unpredictable weather.





 

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