Head out for an action-packed morning at Woodhill Mountain Bike Park. Don't worry if you don't have your own bike, you can hire one out there. There is over 100km of purpose-built single track with more than 250 man-made features, so go mad and have fun (approx 30 mins from the central city).
The perfect relaxation after this is a drive to the east side of the Kaipara Coast Highway between Kaukapakapa and the Makarau River to Omeru Scenic Reserve. If you're hungry after all that biking, make sure you go via Waimauku Food Station (it will only take five minutes extra). Amazing fish and chips and great extras like fish tacos, marinated fish salad, risotto or whatever the chef feels like making that day. At the reserve there's a series of three waterfalls: Waitangi Falls, Omeru Falls and Waitangi Stream Cascade where you can cool down with a serene swim in a gorgeous green environment. You won't believe what's hidden away down there (around 30 mins from Woodhill Bike Park).
On the way home stop in at the Tasting Shed. The setting is so exquisitely New Zealand, with its plywood sheds, rough-sawn timber decking and easy transitions from indoors to out, and all of it gracefully and artfully put together. This is coupled with exciting and original dishes that won't break the budget - not one is over the $25 mark.
Pack up your togs, towel and picnic rug and head out on SH16. Gather some picnic items on your way: gourmet goods, cheeses, bread, cured meats, delicatessen items and produce from Boric Food Market in Kumeu (make sure you stop for a coffee in their sprawling outdoor area); wine from Soljans, Kumeu River, Matua, Coopers Creek or any of the other vineyards; artisan bread and fabulous pastries from Gourmet Gannet Kitchen in Huapai; or fantastic pies baked on site at The Food Vault, also in Huapai (around 25 minutes from the central city).
Keep driving to Shelly Beach and work up an appetite with a beach walk or swim before your picnic with a view of the mighty Kaipara harbour. Laze as long as the day takes you, time goes slow in these parts (approx 35 minutes from Huapai).
Meander back through to the Coatesville-Riverhead highway for a craft beer tasting paddle at Hallertau Brewbar and Restaurant. Smaller samplers of all their current brews will help you decide which one you fancy as you settle in for some serious relaxation (around 40 mins from Shelly Beach).