Spare battery, charger, bike helmet, day bike backpack (approx. 20 liters) with rain cover, comfortable sports shoes, possibly cycling shoes, weather-appropriate and durable clothing in multiple layers, possibly cycling jersey, possibly cycling gloves, air pump, bike tools, sun and rain protection, provisions and drinking water, water bottle and suitable holder, first aid kit, pocket knife, mobile phone, possibly phone holder for the handlebars, possibly headlamp and reflectors, maps