Arrochar Alps from Loch Lomond Scotland antique print. Loch Lomond with a view across the water to Tarbet and The Cobbler mountains, in the Arrochar Alps. Tarbet & The Cobbler are mountains in the Arrochar Alps a group of mountains located around the head of Loch Long, Loch Fyne,and Loch Goil, near the villages of Arrochar and Lochgoilhead, on the Cowal Peninsula in Argyll and Bute, Scotland. The mountains are especially popular with hillwalkers, due to their proximity and accessibility from Glasgow. They are largely within the Loch Lomond and the Trossachs National Park and in part also extend into the Argyll Forest Park. Glens which go into the heart of the range include: Glen Croe, Hell’s Glen and Glen Kinglass. Loch Lomond is a freshwater loch lying on the Highland Boundary Fault, often considered the boundary between the lowlands of Central Scotland and the Highlands. It is 24 miles (39 km) long and between 0.75 and 5 miles (1.21 and 8.05 km) wide. It has an average depth of about 121 feet (37 m), and a maximum depth of about 620 feet (190 m). Its surface area is 27 sq mi (70 km2), and it has a volume of 0.62 cu mi (2.6 km3). Of all the lochs and lakes in Great Britain, it is the largest by surface area and the second largest (after Loch Ness) by water volume. Within the United Kingdom, it is surpassed only by Lough Neagh and Lough Erne in Northern Ireland and regarding the British Isles as a whole, there are also several larger loughs in the Republic of Ireland.