The approach to Everest Base Camp is clearly the focus of many trekkers when they come to Nepal. This high austere region on the border with Tibet with its brilliant light and azure skies contains many possible treks and variations, but the magnetic draw towards Everest is paramount and the views from either the peak of Kala Pattar near to Everest Base Camp or from Gokyo Peak near the Gokyo lakes reveals fabulous views of many of the great peaks with heights in excess of 8000 metres: Cho Oyu (8153m), Everest (8848m), Lhotse (8501m), Makalu (8475m).
The majority of trekkers fly into the narrow airstrip at Lukla (2800m) but unless time is limited, it is highly recommended to take a bus to Jiri from Kathmandu and then walk in to Namche Bazaar on a tough trek of about ten days, through spectacular scenery as the trail cuts across the flow of the river valleys through forests of pine and rhododendron. This also provides good acclimatization and assures you that you will not suffer from flight cancellations on the Kathmandu to Lukla route.
A winter trek in this region is possible. In recent years there has been a tendency for drier winters to occur as the normal moist airflow from the Mediterranean has been interrupted or delayed. However, sudden snowfall can occur at any time at the higher altitudes. Trekking in winter, from December to February, has the advantage that the trails are practically empty, whereas it is acknowledged that in the peak trekking season in September to November, the lodges on the Everest Base Camp trek are packed and the trails very busy.
Whenever you decide to come, it must be remembered that this is a high trek, so acclimatization is normal at Namche Bazaar (one day) and perhaps an extra day further on as well.